Python基础(二)

阳光穿透心脏的1/2处 2022-04-23 08:38 224阅读 0赞

转载：[https://www.cnblogs.com/wupeiqi/articles/4911365.html][https_www.cnblogs.com_wupeiqi_articles_4911365.html]

**目录**

入门知识拾遗

一、作用域

二、三元运算

三、进制

Python基础

一、整数

二、长整型

三、浮点型

四、字符串

五、列表

六、元组

七、字典

八、set集合

九、collection系列

迭代器和生成器

一、迭代器

二、生成器

三、深浅拷贝

--------------------

# 入门知识拾遗 #

## **一、作用域** ##

对于变量的作用域，执行声明并在内存中存在，该变量就可以在下面的代码中使用。

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> </td> 
   <td> <p><code>if</code>&nbsp;<code>1</code><code>=</code><code>=</code><code>1</code><code>:</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>name&nbsp;</code><code>=</code>&nbsp;<code>'wupeiqi'</code></p> <p><code>print</code>&nbsp;&nbsp;<code>name</code></p> </td> 
  </tr> 
 </tbody> 
</table>

**下面的结论对吗？**

> 外层变量，可以被内层变量使用
> 
> 内层变量，无法被外层变量使用

## **二、三元运算** ##

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> </td> 
   <td> <p><code>result&nbsp;</code><code>=</code>&nbsp;<code>值</code><code>1</code>&nbsp;<code>if</code>&nbsp;<code>条件&nbsp;</code><code>else</code>&nbsp;<code>值</code><code>2</code></p> </td> 
  </tr> 
 </tbody> 
</table>

如果条件为真：result = 值1  
如果条件为假：result = 值2

## **三、进制** ##

*  二进制，01
 *  八进制，01234567
 *  十进制，0123456789
 *  十六进制，0123456789ABCDEF

# Python基础 #

**对于Python，一切事物都是对象，对象基于类创建**

![425762-20151031133946575-1667336241.png][]

所以，以下这些值都是对象： "wupeiqi"、38、\['北京', '上海', '深圳'\]，并且是根据不同的类生成的对象。

![425762-20151031134228200-1953404420.png][]![425762-20151031134348685-1255331039.png][]![425762-20151031134548575-1768286588.png][]

## **一、整数** ##

如： 18、73、84

每一个整数都具备如下功能：

class int(object):
        """
        int(x=0) -> int or long
        int(x, base=10) -> int or long
        
        Convert a number or string to an integer, or return 0 if no arguments
        are given.  If x is floating point, the conversion truncates towards zero.
        If x is outside the integer range, the function returns a long instead.
        
        If x is not a number or if base is given, then x must be a string or
        Unicode object representing an integer literal in the given base.  The
        literal can be preceded by '+' or '-' and be surrounded by whitespace.
        The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
        interpret the base from the string as an integer literal.
        >>> int('0b100', base=0)
        4
        """
        def bit_length(self): 
            """ 返回表示该数字的时占用的最少位数 """
            """
            int.bit_length() -> int
            
            Number of bits necessary to represent self in binary.
            >>> bin(37)
            '0b100101'
            >>> (37).bit_length()
            6
            """
            return 0
    
        def conjugate(self, *args, **kwargs): # real signature unknown
            """ 返回该复数的共轭复数 """
            """ Returns self, the complex conjugate of any int. """
            pass
    
        def __abs__(self):
            """ 返回绝对值 """
            """ x.__abs__() <==> abs(x) """
            pass
    
        def __add__(self, y):
            """ x.__add__(y) <==> x+y """
            pass
    
        def __and__(self, y):
            """ x.__and__(y) <==> x&y """
            pass
    
        def __cmp__(self, y): 
            """ 比较两个数大小 """
            """ x.__cmp__(y) <==> cmp(x,y) """
            pass
    
        def __coerce__(self, y):
            """ 强制生成一个元组 """ 
            """ x.__coerce__(y) <==> coerce(x, y) """
            pass
    
        def __divmod__(self, y): 
            """ 相除，得到商和余数组成的元组 """ 
            """ x.__divmod__(y) <==> divmod(x, y) """
            pass
    
        def __div__(self, y): 
            """ x.__div__(y) <==> x/y """
            pass
    
        def __float__(self): 
            """ 转换为浮点类型 """ 
            """ x.__float__() <==> float(x) """
            pass
    
        def __floordiv__(self, y): 
            """ x.__floordiv__(y) <==> x//y """
            pass
    
        def __format__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __getattribute__(self, name): 
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getnewargs__(self, *args, **kwargs): # real signature unknown
            """ 内部调用 __new__方法或创建对象时传入参数使用 """ 
            pass
    
        def __hash__(self): 
            """如果对象object为哈希表类型，返回对象object的哈希值。哈希值为整数。在字典查找中，哈希值用于快速比较字典的键。两个数值如果相等，则哈希值也相等。"""
            """ x.__hash__() <==> hash(x) """
            pass
    
        def __hex__(self): 
            """ 返回当前数的 十六进制 表示 """ 
            """ x.__hex__() <==> hex(x) """
            pass
    
        def __index__(self): 
            """ 用于切片，数字无意义 """
            """ x[y:z] <==> x[y.__index__():z.__index__()] """
            pass
    
        def __init__(self, x, base=10): # known special case of int.__init__
            """ 构造方法，执行 x = 123 或 x = int(10) 时，自动调用，暂时忽略 """ 
            """
            int(x=0) -> int or long
            int(x, base=10) -> int or long
            
            Convert a number or string to an integer, or return 0 if no arguments
            are given.  If x is floating point, the conversion truncates towards zero.
            If x is outside the integer range, the function returns a long instead.
            
            If x is not a number or if base is given, then x must be a string or
            Unicode object representing an integer literal in the given base.  The
            literal can be preceded by '+' or '-' and be surrounded by whitespace.
            The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
            interpret the base from the string as an integer literal.
            >>> int('0b100', base=0)
            4
            # (copied from class doc)
            """
            pass
    
        def __int__(self): 
            """ 转换为整数 """ 
            """ x.__int__() <==> int(x) """
            pass
    
        def __invert__(self): 
            """ x.__invert__() <==> ~x """
            pass
    
        def __long__(self): 
            """ 转换为长整数 """ 
            """ x.__long__() <==> long(x) """
            pass
    
        def __lshift__(self, y): 
            """ x.__lshift__(y) <==> x<<y """
            pass
    
        def __mod__(self, y): 
            """ x.__mod__(y) <==> x%y """
            pass
    
        def __mul__(self, y): 
            """ x.__mul__(y) <==> x*y """
            pass
    
        def __neg__(self): 
            """ x.__neg__() <==> -x """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): 
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __nonzero__(self): 
            """ x.__nonzero__() <==> x != 0 """
            pass
    
        def __oct__(self): 
            """ 返回改值的 八进制 表示 """ 
            """ x.__oct__() <==> oct(x) """
            pass
    
        def __or__(self, y): 
            """ x.__or__(y) <==> x|y """
            pass
    
        def __pos__(self): 
            """ x.__pos__() <==> +x """
            pass
    
        def __pow__(self, y, z=None): 
            """ 幂，次方 """ 
            """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __radd__(self, y): 
            """ x.__radd__(y) <==> y+x """
            pass
    
        def __rand__(self, y): 
            """ x.__rand__(y) <==> y&x """
            pass
    
        def __rdivmod__(self, y): 
            """ x.__rdivmod__(y) <==> divmod(y, x) """
            pass
    
        def __rdiv__(self, y): 
            """ x.__rdiv__(y) <==> y/x """
            pass
    
        def __repr__(self): 
            """转化为解释器可读取的形式 """
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __str__(self): 
            """转换为人阅读的形式，如果没有适于人阅读的解释形式的话，则返回解释器课阅读的形式"""
            """ x.__str__() <==> str(x) """
            pass
    
        def __rfloordiv__(self, y): 
            """ x.__rfloordiv__(y) <==> y//x """
            pass
    
        def __rlshift__(self, y): 
            """ x.__rlshift__(y) <==> y<<x """
            pass
    
        def __rmod__(self, y): 
            """ x.__rmod__(y) <==> y%x """
            pass
    
        def __rmul__(self, y): 
            """ x.__rmul__(y) <==> y*x """
            pass
    
        def __ror__(self, y): 
            """ x.__ror__(y) <==> y|x """
            pass
    
        def __rpow__(self, x, z=None): 
            """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __rrshift__(self, y): 
            """ x.__rrshift__(y) <==> y>>x """
            pass
    
        def __rshift__(self, y): 
            """ x.__rshift__(y) <==> x>>y """
            pass
    
        def __rsub__(self, y): 
            """ x.__rsub__(y) <==> y-x """
            pass
    
        def __rtruediv__(self, y): 
            """ x.__rtruediv__(y) <==> y/x """
            pass
    
        def __rxor__(self, y): 
            """ x.__rxor__(y) <==> y^x """
            pass
    
        def __sub__(self, y): 
            """ x.__sub__(y) <==> x-y """
            pass
    
        def __truediv__(self, y): 
            """ x.__truediv__(y) <==> x/y """
            pass
    
        def __trunc__(self, *args, **kwargs): 
            """ 返回数值被截取为整形的值，在整形中无意义 """
            pass
    
        def __xor__(self, y): 
            """ x.__xor__(y) <==> x^y """
            pass
    
        denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 分母 = 1 """
        """the denominator of a rational number in lowest terms"""
    
        imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 虚数，无意义 """
        """the imaginary part of a complex number"""
    
        numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 分子 = 数字大小 """
        """the numerator of a rational number in lowest terms"""
    
        real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """ 实属，无意义 """
        """the real part of a complex number"""

## **二、长整型** ##

可能如：2147483649、9223372036854775807

每个长整型都具备如下功能：

class long(object):
        """
        long(x=0) -> long
        long(x, base=10) -> long
        
        Convert a number or string to a long integer, or return 0L if no arguments
        are given.  If x is floating point, the conversion truncates towards zero.
        
        If x is not a number or if base is given, then x must be a string or
        Unicode object representing an integer literal in the given base.  The
        literal can be preceded by '+' or '-' and be surrounded by whitespace.
        The base defaults to 10.  Valid bases are 0 and 2-36.  Base 0 means to
        interpret the base from the string as an integer literal.
        >>> int('0b100', base=0)
        4L
        """
        def bit_length(self): # real signature unknown; restored from __doc__
            """
            long.bit_length() -> int or long
            
            Number of bits necessary to represent self in binary.
            >>> bin(37L)
            '0b100101'
            >>> (37L).bit_length()
            6
            """
            return 0
    
        def conjugate(self, *args, **kwargs): # real signature unknown
            """ Returns self, the complex conjugate of any long. """
            pass
    
        def __abs__(self): # real signature unknown; restored from __doc__
            """ x.__abs__() <==> abs(x) """
            pass
    
        def __add__(self, y): # real signature unknown; restored from __doc__
            """ x.__add__(y) <==> x+y """
            pass
    
        def __and__(self, y): # real signature unknown; restored from __doc__
            """ x.__and__(y) <==> x&y """
            pass
    
        def __cmp__(self, y): # real signature unknown; restored from __doc__
            """ x.__cmp__(y) <==> cmp(x,y) """
            pass
    
        def __coerce__(self, y): # real signature unknown; restored from __doc__
            """ x.__coerce__(y) <==> coerce(x, y) """
            pass
    
        def __divmod__(self, y): # real signature unknown; restored from __doc__
            """ x.__divmod__(y) <==> divmod(x, y) """
            pass
    
        def __div__(self, y): # real signature unknown; restored from __doc__
            """ x.__div__(y) <==> x/y """
            pass
    
        def __float__(self): # real signature unknown; restored from __doc__
            """ x.__float__() <==> float(x) """
            pass
    
        def __floordiv__(self, y): # real signature unknown; restored from __doc__
            """ x.__floordiv__(y) <==> x//y """
            pass
    
        def __format__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getnewargs__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __hash__(self): # real signature unknown; restored from __doc__
            """ x.__hash__() <==> hash(x) """
            pass
    
        def __hex__(self): # real signature unknown; restored from __doc__
            """ x.__hex__() <==> hex(x) """
            pass
    
        def __index__(self): # real signature unknown; restored from __doc__
            """ x[y:z] <==> x[y.__index__():z.__index__()] """
            pass
    
        def __init__(self, x=0): # real signature unknown; restored from __doc__
            pass
    
        def __int__(self): # real signature unknown; restored from __doc__
            """ x.__int__() <==> int(x) """
            pass
    
        def __invert__(self): # real signature unknown; restored from __doc__
            """ x.__invert__() <==> ~x """
            pass
    
        def __long__(self): # real signature unknown; restored from __doc__
            """ x.__long__() <==> long(x) """
            pass
    
        def __lshift__(self, y): # real signature unknown; restored from __doc__
            """ x.__lshift__(y) <==> x<<y """
            pass
    
        def __mod__(self, y): # real signature unknown; restored from __doc__
            """ x.__mod__(y) <==> x%y """
            pass
    
        def __mul__(self, y): # real signature unknown; restored from __doc__
            """ x.__mul__(y) <==> x*y """
            pass
    
        def __neg__(self): # real signature unknown; restored from __doc__
            """ x.__neg__() <==> -x """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __nonzero__(self): # real signature unknown; restored from __doc__
            """ x.__nonzero__() <==> x != 0 """
            pass
    
        def __oct__(self): # real signature unknown; restored from __doc__
            """ x.__oct__() <==> oct(x) """
            pass
    
        def __or__(self, y): # real signature unknown; restored from __doc__
            """ x.__or__(y) <==> x|y """
            pass
    
        def __pos__(self): # real signature unknown; restored from __doc__
            """ x.__pos__() <==> +x """
            pass
    
        def __pow__(self, y, z=None): # real signature unknown; restored from __doc__
            """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __radd__(self, y): # real signature unknown; restored from __doc__
            """ x.__radd__(y) <==> y+x """
            pass
    
        def __rand__(self, y): # real signature unknown; restored from __doc__
            """ x.__rand__(y) <==> y&x """
            pass
    
        def __rdivmod__(self, y): # real signature unknown; restored from __doc__
            """ x.__rdivmod__(y) <==> divmod(y, x) """
            pass
    
        def __rdiv__(self, y): # real signature unknown; restored from __doc__
            """ x.__rdiv__(y) <==> y/x """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __rfloordiv__(self, y): # real signature unknown; restored from __doc__
            """ x.__rfloordiv__(y) <==> y//x """
            pass
    
        def __rlshift__(self, y): # real signature unknown; restored from __doc__
            """ x.__rlshift__(y) <==> y<<x """
            pass
    
        def __rmod__(self, y): # real signature unknown; restored from __doc__
            """ x.__rmod__(y) <==> y%x """
            pass
    
        def __rmul__(self, y): # real signature unknown; restored from __doc__
            """ x.__rmul__(y) <==> y*x """
            pass
    
        def __ror__(self, y): # real signature unknown; restored from __doc__
            """ x.__ror__(y) <==> y|x """
            pass
    
        def __rpow__(self, x, z=None): # real signature unknown; restored from __doc__
            """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __rrshift__(self, y): # real signature unknown; restored from __doc__
            """ x.__rrshift__(y) <==> y>>x """
            pass
    
        def __rshift__(self, y): # real signature unknown; restored from __doc__
            """ x.__rshift__(y) <==> x>>y """
            pass
    
        def __rsub__(self, y): # real signature unknown; restored from __doc__
            """ x.__rsub__(y) <==> y-x """
            pass
    
        def __rtruediv__(self, y): # real signature unknown; restored from __doc__
            """ x.__rtruediv__(y) <==> y/x """
            pass
    
        def __rxor__(self, y): # real signature unknown; restored from __doc__
            """ x.__rxor__(y) <==> y^x """
            pass
    
        def __sizeof__(self, *args, **kwargs): # real signature unknown
            """ Returns size in memory, in bytes """
            pass
    
        def __str__(self): # real signature unknown; restored from __doc__
            """ x.__str__() <==> str(x) """
            pass
    
        def __sub__(self, y): # real signature unknown; restored from __doc__
            """ x.__sub__(y) <==> x-y """
            pass
    
        def __truediv__(self, y): # real signature unknown; restored from __doc__
            """ x.__truediv__(y) <==> x/y """
            pass
    
        def __trunc__(self, *args, **kwargs): # real signature unknown
            """ Truncating an Integral returns itself. """
            pass
    
        def __xor__(self, y): # real signature unknown; restored from __doc__
            """ x.__xor__(y) <==> x^y """
            pass
    
        denominator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """the denominator of a rational number in lowest terms"""
    
        imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """the imaginary part of a complex number"""
    
        numerator = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """the numerator of a rational number in lowest terms"""
    
        real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """the real part of a complex number"""

## **三、浮点型** ##

如：3.14、2.88

每个浮点型都具备如下功能：

class float(object):
        """
        float(x) -> floating point number
        
        Convert a string or number to a floating point number, if possible.
        """
        def as_integer_ratio(self):   
            """ 获取改值的最简比 """
            """
            float.as_integer_ratio() -> (int, int)
    
            Return a pair of integers, whose ratio is exactly equal to the original
            float and with a positive denominator.
            Raise OverflowError on infinities and a ValueError on NaNs.
    
            >>> (10.0).as_integer_ratio()
            (10, 1)
            >>> (0.0).as_integer_ratio()
            (0, 1)
            >>> (-.25).as_integer_ratio()
            (-1, 4)
            """
            pass
    
        def conjugate(self, *args, **kwargs): # real signature unknown
            """ Return self, the complex conjugate of any float. """
            pass
    
        def fromhex(self, string):   
            """ 将十六进制字符串转换成浮点型 """
            """
            float.fromhex(string) -> float
            
            Create a floating-point number from a hexadecimal string.
            >>> float.fromhex('0x1.ffffp10')
            2047.984375
            >>> float.fromhex('-0x1p-1074')
            -4.9406564584124654e-324
            """
            return 0.0
    
        def hex(self):   
            """ 返回当前值的 16 进制表示 """
            """
            float.hex() -> string
            
            Return a hexadecimal representation of a floating-point number.
            >>> (-0.1).hex()
            '-0x1.999999999999ap-4'
            >>> 3.14159.hex()
            '0x1.921f9f01b866ep+1'
            """
            return ""
    
        def is_integer(self, *args, **kwargs): # real signature unknown
            """ Return True if the float is an integer. """
            pass
    
        def __abs__(self):   
            """ x.__abs__() <==> abs(x) """
            pass
    
        def __add__(self, y):   
            """ x.__add__(y) <==> x+y """
            pass
    
        def __coerce__(self, y):   
            """ x.__coerce__(y) <==> coerce(x, y) """
            pass
    
        def __divmod__(self, y):   
            """ x.__divmod__(y) <==> divmod(x, y) """
            pass
    
        def __div__(self, y):   
            """ x.__div__(y) <==> x/y """
            pass
    
        def __eq__(self, y):   
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __float__(self):   
            """ x.__float__() <==> float(x) """
            pass
    
        def __floordiv__(self, y):   
            """ x.__floordiv__(y) <==> x//y """
            pass
    
        def __format__(self, format_spec):   
            """
            float.__format__(format_spec) -> string
            
            Formats the float according to format_spec.
            """
            return ""
    
        def __getattribute__(self, name):   
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getformat__(self, typestr):   
            """
            float.__getformat__(typestr) -> string
            
            You probably don't want to use this function.  It exists mainly to be
            used in Python's test suite.
            
            typestr must be 'double' or 'float'.  This function returns whichever of
            'unknown', 'IEEE, big-endian' or 'IEEE, little-endian' best describes the
            format of floating point numbers used by the C type named by typestr.
            """
            return ""
    
        def __getnewargs__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __ge__(self, y):   
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y):   
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __hash__(self):   
            """ x.__hash__() <==> hash(x) """
            pass
    
        def __init__(self, x):   
            pass
    
        def __int__(self):   
            """ x.__int__() <==> int(x) """
            pass
    
        def __le__(self, y):   
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __long__(self):   
            """ x.__long__() <==> long(x) """
            pass
    
        def __lt__(self, y):   
            """ x.__lt__(y) <==> x<y """
            pass
    
        def __mod__(self, y):   
            """ x.__mod__(y) <==> x%y """
            pass
    
        def __mul__(self, y):   
            """ x.__mul__(y) <==> x*y """
            pass
    
        def __neg__(self):   
            """ x.__neg__() <==> -x """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more):   
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y):   
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __nonzero__(self):   
            """ x.__nonzero__() <==> x != 0 """
            pass
    
        def __pos__(self):   
            """ x.__pos__() <==> +x """
            pass
    
        def __pow__(self, y, z=None):   
            """ x.__pow__(y[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __radd__(self, y):   
            """ x.__radd__(y) <==> y+x """
            pass
    
        def __rdivmod__(self, y):   
            """ x.__rdivmod__(y) <==> divmod(y, x) """
            pass
    
        def __rdiv__(self, y):   
            """ x.__rdiv__(y) <==> y/x """
            pass
    
        def __repr__(self):   
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __rfloordiv__(self, y):   
            """ x.__rfloordiv__(y) <==> y//x """
            pass
    
        def __rmod__(self, y):   
            """ x.__rmod__(y) <==> y%x """
            pass
    
        def __rmul__(self, y):   
            """ x.__rmul__(y) <==> y*x """
            pass
    
        def __rpow__(self, x, z=None):   
            """ y.__rpow__(x[, z]) <==> pow(x, y[, z]) """
            pass
    
        def __rsub__(self, y):   
            """ x.__rsub__(y) <==> y-x """
            pass
    
        def __rtruediv__(self, y):   
            """ x.__rtruediv__(y) <==> y/x """
            pass
    
        def __setformat__(self, typestr, fmt):   
            """
            float.__setformat__(typestr, fmt) -> None
            
            You probably don't want to use this function.  It exists mainly to be
            used in Python's test suite.
            
            typestr must be 'double' or 'float'.  fmt must be one of 'unknown',
            'IEEE, big-endian' or 'IEEE, little-endian', and in addition can only be
            one of the latter two if it appears to match the underlying C reality.
            
            Override the automatic determination of C-level floating point type.
            This affects how floats are converted to and from binary strings.
            """
            pass
    
        def __str__(self):   
            """ x.__str__() <==> str(x) """
            pass
    
        def __sub__(self, y):   
            """ x.__sub__(y) <==> x-y """
            pass
    
        def __truediv__(self, y):   
            """ x.__truediv__(y) <==> x/y """
            pass
    
        def __trunc__(self, *args, **kwargs): # real signature unknown
            """ Return the Integral closest to x between 0 and x. """
            pass
    
        imag = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """the imaginary part of a complex number"""
    
        real = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
        """the real part of a complex number"""
    
    float

## **四、字符串** ##

如：'wupeiqi'、'alex'

每个字符串都具备如下功能：

class str(basestring):
        """
        str(object='') -> string
        
        Return a nice string representation of the object.
        If the argument is a string, the return value is the same object.
        """
        def capitalize(self):  
            """ 首字母变大写 """
            """
            S.capitalize() -> string
            
            Return a copy of the string S with only its first character
            capitalized.
            """
            return ""
    
        def center(self, width, fillchar=None):  
            """ 内容居中，width：总长度；fillchar：空白处填充内容，默认无 """
            """
            S.center(width[, fillchar]) -> string
            
            Return S centered in a string of length width. Padding is
            done using the specified fill character (default is a space)
            """
            return ""
    
        def count(self, sub, start=None, end=None):  
            """ 子序列个数 """
            """
            S.count(sub[, start[, end]]) -> int
            
            Return the number of non-overlapping occurrences of substring sub in
            string S[start:end].  Optional arguments start and end are interpreted
            as in slice notation.
            """
            return 0
    
        def decode(self, encoding=None, errors=None):  
            """ 解码 """
            """
            S.decode([encoding[,errors]]) -> object
            
            Decodes S using the codec registered for encoding. encoding defaults
            to the default encoding. errors may be given to set a different error
            handling scheme. Default is 'strict' meaning that encoding errors raise
            a UnicodeDecodeError. Other possible values are 'ignore' and 'replace'
            as well as any other name registered with codecs.register_error that is
            able to handle UnicodeDecodeErrors.
            """
            return object()
    
        def encode(self, encoding=None, errors=None):  
            """ 编码，针对unicode """
            """
            S.encode([encoding[,errors]]) -> object
            
            Encodes S using the codec registered for encoding. encoding defaults
            to the default encoding. errors may be given to set a different error
            handling scheme. Default is 'strict' meaning that encoding errors raise
            a UnicodeEncodeError. Other possible values are 'ignore', 'replace' and
            'xmlcharrefreplace' as well as any other name registered with
            codecs.register_error that is able to handle UnicodeEncodeErrors.
            """
            return object()
    
        def endswith(self, suffix, start=None, end=None):  
            """ 是否以 xxx 结束 """
            """
            S.endswith(suffix[, start[, end]]) -> bool
            
            Return True if S ends with the specified suffix, False otherwise.
            With optional start, test S beginning at that position.
            With optional end, stop comparing S at that position.
            suffix can also be a tuple of strings to try.
            """
            return False
    
        def expandtabs(self, tabsize=None):  
            """ 将tab转换成空格，默认一个tab转换成8个空格 """
            """
            S.expandtabs([tabsize]) -> string
            
            Return a copy of S where all tab characters are expanded using spaces.
            If tabsize is not given, a tab size of 8 characters is assumed.
            """
            return ""
    
        def find(self, sub, start=None, end=None):  
            """ 寻找子序列位置，如果没找到，返回 -1 """
            """
            S.find(sub [,start [,end]]) -> int
            
            Return the lowest index in S where substring sub is found,
            such that sub is contained within S[start:end].  Optional
            arguments start and end are interpreted as in slice notation.
            
            Return -1 on failure.
            """
            return 0
    
        def format(*args, **kwargs): # known special case of str.format
            """ 字符串格式化，动态参数，将函数式编程时细说 """
            """
            S.format(*args, **kwargs) -> string
            
            Return a formatted version of S, using substitutions from args and kwargs.
            The substitutions are identified by braces ('{' and '}').
            """
            pass
    
        def index(self, sub, start=None, end=None):  
            """ 子序列位置，如果没找到，报错 """
            S.index(sub [,start [,end]]) -> int
            
            Like S.find() but raise ValueError when the substring is not found.
            """
            return 0
    
        def isalnum(self):  
            """ 是否是字母和数字 """
            """
            S.isalnum() -> bool
            
            Return True if all characters in S are alphanumeric
            and there is at least one character in S, False otherwise.
            """
            return False
    
        def isalpha(self):  
            """ 是否是字母 """
            """
            S.isalpha() -> bool
            
            Return True if all characters in S are alphabetic
            and there is at least one character in S, False otherwise.
            """
            return False
    
        def isdigit(self):  
            """ 是否是数字 """
            """
            S.isdigit() -> bool
            
            Return True if all characters in S are digits
            and there is at least one character in S, False otherwise.
            """
            return False
    
        def islower(self):  
            """ 是否小写 """
            """
            S.islower() -> bool
            
            Return True if all cased characters in S are lowercase and there is
            at least one cased character in S, False otherwise.
            """
            return False
    
        def isspace(self):  
            """
            S.isspace() -> bool
            
            Return True if all characters in S are whitespace
            and there is at least one character in S, False otherwise.
            """
            return False
    
        def istitle(self):  
            """
            S.istitle() -> bool
            
            Return True if S is a titlecased string and there is at least one
            character in S, i.e. uppercase characters may only follow uncased
            characters and lowercase characters only cased ones. Return False
            otherwise.
            """
            return False
    
        def isupper(self):  
            """
            S.isupper() -> bool
            
            Return True if all cased characters in S are uppercase and there is
            at least one cased character in S, False otherwise.
            """
            return False
    
        def join(self, iterable):  
            """ 连接 """
            """
            S.join(iterable) -> string
            
            Return a string which is the concatenation of the strings in the
            iterable.  The separator between elements is S.
            """
            return ""
    
        def ljust(self, width, fillchar=None):  
            """ 内容左对齐，右侧填充 """
            """
            S.ljust(width[, fillchar]) -> string
            
            Return S left-justified in a string of length width. Padding is
            done using the specified fill character (default is a space).
            """
            return ""
    
        def lower(self):  
            """ 变小写 """
            """
            S.lower() -> string
            
            Return a copy of the string S converted to lowercase.
            """
            return ""
    
        def lstrip(self, chars=None):  
            """ 移除左侧空白 """
            """
            S.lstrip([chars]) -> string or unicode
            
            Return a copy of the string S with leading whitespace removed.
            If chars is given and not None, remove characters in chars instead.
            If chars is unicode, S will be converted to unicode before stripping
            """
            return ""
    
        def partition(self, sep):  
            """ 分割，前，中，后三部分 """
            """
            S.partition(sep) -> (head, sep, tail)
            
            Search for the separator sep in S, and return the part before it,
            the separator itself, and the part after it.  If the separator is not
            found, return S and two empty strings.
            """
            pass
    
        def replace(self, old, new, count=None):  
            """ 替换 """
            """
            S.replace(old, new[, count]) -> string
            
            Return a copy of string S with all occurrences of substring
            old replaced by new.  If the optional argument count is
            given, only the first count occurrences are replaced.
            """
            return ""
    
        def rfind(self, sub, start=None, end=None):  
            """
            S.rfind(sub [,start [,end]]) -> int
            
            Return the highest index in S where substring sub is found,
            such that sub is contained within S[start:end].  Optional
            arguments start and end are interpreted as in slice notation.
            
            Return -1 on failure.
            """
            return 0
    
        def rindex(self, sub, start=None, end=None):  
            """
            S.rindex(sub [,start [,end]]) -> int
            
            Like S.rfind() but raise ValueError when the substring is not found.
            """
            return 0
    
        def rjust(self, width, fillchar=None):  
            """
            S.rjust(width[, fillchar]) -> string
            
            Return S right-justified in a string of length width. Padding is
            done using the specified fill character (default is a space)
            """
            return ""
    
        def rpartition(self, sep):  
            """
            S.rpartition(sep) -> (head, sep, tail)
            
            Search for the separator sep in S, starting at the end of S, and return
            the part before it, the separator itself, and the part after it.  If the
            separator is not found, return two empty strings and S.
            """
            pass
    
        def rsplit(self, sep=None, maxsplit=None):  
            """
            S.rsplit([sep [,maxsplit]]) -> list of strings
            
            Return a list of the words in the string S, using sep as the
            delimiter string, starting at the end of the string and working
            to the front.  If maxsplit is given, at most maxsplit splits are
            done. If sep is not specified or is None, any whitespace string
            is a separator.
            """
            return []
    
        def rstrip(self, chars=None):  
            """
            S.rstrip([chars]) -> string or unicode
            
            Return a copy of the string S with trailing whitespace removed.
            If chars is given and not None, remove characters in chars instead.
            If chars is unicode, S will be converted to unicode before stripping
            """
            return ""
    
        def split(self, sep=None, maxsplit=None):  
            """ 分割， maxsplit最多分割几次 """
            """
            S.split([sep [,maxsplit]]) -> list of strings
            
            Return a list of the words in the string S, using sep as the
            delimiter string.  If maxsplit is given, at most maxsplit
            splits are done. If sep is not specified or is None, any
            whitespace string is a separator and empty strings are removed
            from the result.
            """
            return []
    
        def splitlines(self, keepends=False):  
            """ 根据换行分割 """
            """
            S.splitlines(keepends=False) -> list of strings
            
            Return a list of the lines in S, breaking at line boundaries.
            Line breaks are not included in the resulting list unless keepends
            is given and true.
            """
            return []
    
        def startswith(self, prefix, start=None, end=None):  
            """ 是否起始 """
            """
            S.startswith(prefix[, start[, end]]) -> bool
            
            Return True if S starts with the specified prefix, False otherwise.
            With optional start, test S beginning at that position.
            With optional end, stop comparing S at that position.
            prefix can also be a tuple of strings to try.
            """
            return False
    
        def strip(self, chars=None):  
            """ 移除两段空白 """
            """
            S.strip([chars]) -> string or unicode
            
            Return a copy of the string S with leading and trailing
            whitespace removed.
            If chars is given and not None, remove characters in chars instead.
            If chars is unicode, S will be converted to unicode before stripping
            """
            return ""
    
        def swapcase(self):  
            """ 大写变小写，小写变大写 """
            """
            S.swapcase() -> string
            
            Return a copy of the string S with uppercase characters
            converted to lowercase and vice versa.
            """
            return ""
    
        def title(self):  
            """
            S.title() -> string
            
            Return a titlecased version of S, i.e. words start with uppercase
            characters, all remaining cased characters have lowercase.
            """
            return ""
    
        def translate(self, table, deletechars=None):  
            """
            转换，需要先做一个对应表，最后一个表示删除字符集合
            intab = "aeiou"
            outtab = "12345"
            trantab = maketrans(intab, outtab)
            str = "this is string example....wow!!!"
            print str.translate(trantab, 'xm')
            """
    
            """
            S.translate(table [,deletechars]) -> string
            
            Return a copy of the string S, where all characters occurring
            in the optional argument deletechars are removed, and the
            remaining characters have been mapped through the given
            translation table, which must be a string of length 256 or None.
            If the table argument is None, no translation is applied and
            the operation simply removes the characters in deletechars.
            """
            return ""
    
        def upper(self):  
            """
            S.upper() -> string
            
            Return a copy of the string S converted to uppercase.
            """
            return ""
    
        def zfill(self, width):  
            """方法返回指定长度的字符串，原字符串右对齐，前面填充0。"""
            """
            S.zfill(width) -> string
            
            Pad a numeric string S with zeros on the left, to fill a field
            of the specified width.  The string S is never truncated.
            """
            return ""
    
        def _formatter_field_name_split(self, *args, **kwargs): # real signature unknown
            pass
    
        def _formatter_parser(self, *args, **kwargs): # real signature unknown
            pass
    
        def __add__(self, y):  
            """ x.__add__(y) <==> x+y """
            pass
    
        def __contains__(self, y):  
            """ x.__contains__(y) <==> y in x """
            pass
    
        def __eq__(self, y):  
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __format__(self, format_spec):  
            """
            S.__format__(format_spec) -> string
            
            Return a formatted version of S as described by format_spec.
            """
            return ""
    
        def __getattribute__(self, name):  
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getitem__(self, y):  
            """ x.__getitem__(y) <==> x[y] """
            pass
    
        def __getnewargs__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __getslice__(self, i, j):  
            """
            x.__getslice__(i, j) <==> x[i:j]
                       
                       Use of negative indices is not supported.
            """
            pass
    
        def __ge__(self, y):  
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y):  
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __hash__(self):  
            """ x.__hash__() <==> hash(x) """
            pass
    
        def __init__(self, string=''): # known special case of str.__init__
            """
            str(object='') -> string
            
            Return a nice string representation of the object.
            If the argument is a string, the return value is the same object.
            # (copied from class doc)
            """
            pass
    
        def __len__(self):  
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y):  
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y):  
            """ x.__lt__(y) <==> x<y """
            pass
    
        def __mod__(self, y):  
            """ x.__mod__(y) <==> x%y """
            pass
    
        def __mul__(self, n):  
            """ x.__mul__(n) <==> x*n """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more):  
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y):  
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __repr__(self):  
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __rmod__(self, y):  
            """ x.__rmod__(y) <==> y%x """
            pass
    
        def __rmul__(self, n):  
            """ x.__rmul__(n) <==> n*x """
            pass
    
        def __sizeof__(self):  
            """ S.__sizeof__() -> size of S in memory, in bytes """
            pass
    
        def __str__(self):  
            """ x.__str__() <==> str(x) """
            pass
    
    str
    
    str

注：编码；字符串的乘法；字符串和格式化

## **五、列表** ##

如：\[11,22,33\]、\['wupeiqi', 'alex'\]

每个列表都具备如下功能：

class list(object):
        """
        list() -> new empty list
        list(iterable) -> new list initialized from iterable's items
        """
        def append(self, p_object): # real signature unknown; restored from __doc__
            """ L.append(object) -- append object to end """
            pass
    
        def count(self, value): # real signature unknown; restored from __doc__
            """ L.count(value) -> integer -- return number of occurrences of value """
            return 0
    
        def extend(self, iterable): # real signature unknown; restored from __doc__
            """ L.extend(iterable) -- extend list by appending elements from the iterable """
            pass
    
        def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
            """
            L.index(value, [start, [stop]]) -> integer -- return first index of value.
            Raises ValueError if the value is not present.
            """
            return 0
    
        def insert(self, index, p_object): # real signature unknown; restored from __doc__
            """ L.insert(index, object) -- insert object before index """
            pass
    
        def pop(self, index=None): # real signature unknown; restored from __doc__
            """
            L.pop([index]) -> item -- remove and return item at index (default last).
            Raises IndexError if list is empty or index is out of range.
            """
            pass
    
        def remove(self, value): # real signature unknown; restored from __doc__
            """
            L.remove(value) -- remove first occurrence of value.
            Raises ValueError if the value is not present.
            """
            pass
    
        def reverse(self): # real signature unknown; restored from __doc__
            """ L.reverse() -- reverse *IN PLACE* """
            pass
    
        def sort(self, cmp=None, key=None, reverse=False): # real signature unknown; restored from __doc__
            """
            L.sort(cmp=None, key=None, reverse=False) -- stable sort *IN PLACE*;
            cmp(x, y) -> -1, 0, 1
            """
            pass
    
        def __add__(self, y): # real signature unknown; restored from __doc__
            """ x.__add__(y) <==> x+y """
            pass
    
        def __contains__(self, y): # real signature unknown; restored from __doc__
            """ x.__contains__(y) <==> y in x """
            pass
    
        def __delitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__delitem__(y) <==> del x[y] """
            pass
    
        def __delslice__(self, i, j): # real signature unknown; restored from __doc__
            """
            x.__delslice__(i, j) <==> del x[i:j]
                       
                       Use of negative indices is not supported.
            """
            pass
    
        def __eq__(self, y): # real signature unknown; restored from __doc__
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__getitem__(y) <==> x[y] """
            pass
    
        def __getslice__(self, i, j): # real signature unknown; restored from __doc__
            """
            x.__getslice__(i, j) <==> x[i:j]
                       
                       Use of negative indices is not supported.
            """
            pass
    
        def __ge__(self, y): # real signature unknown; restored from __doc__
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y): # real signature unknown; restored from __doc__
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __iadd__(self, y): # real signature unknown; restored from __doc__
            """ x.__iadd__(y) <==> x+=y """
            pass
    
        def __imul__(self, y): # real signature unknown; restored from __doc__
            """ x.__imul__(y) <==> x*=y """
            pass
    
        def __init__(self, seq=()): # known special case of list.__init__
            """
            list() -> new empty list
            list(iterable) -> new list initialized from iterable's items
            # (copied from class doc)
            """
            pass
    
        def __iter__(self): # real signature unknown; restored from __doc__
            """ x.__iter__() <==> iter(x) """
            pass
    
        def __len__(self): # real signature unknown; restored from __doc__
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y): # real signature unknown; restored from __doc__
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y): # real signature unknown; restored from __doc__
            """ x.__lt__(y) <==> x<y """
            pass
    
        def __mul__(self, n): # real signature unknown; restored from __doc__
            """ x.__mul__(n) <==> x*n """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y): # real signature unknown; restored from __doc__
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __reversed__(self): # real signature unknown; restored from __doc__
            """ L.__reversed__() -- return a reverse iterator over the list """
            pass
    
        def __rmul__(self, n): # real signature unknown; restored from __doc__
            """ x.__rmul__(n) <==> n*x """
            pass
    
        def __setitem__(self, i, y): # real signature unknown; restored from __doc__
            """ x.__setitem__(i, y) <==> x[i]=y """
            pass
    
        def __setslice__(self, i, j, y): # real signature unknown; restored from __doc__
            """
            x.__setslice__(i, j, y) <==> x[i:j]=y
                       
                       Use  of negative indices is not supported.
            """
            pass
    
        def __sizeof__(self): # real signature unknown; restored from __doc__
            """ L.__sizeof__() -- size of L in memory, in bytes """
            pass
    
        __hash__ = None

注：排序；

## **六、元组** ##

如：(11,22,33)、('wupeiqi', 'alex')

每个元组都具备如下功能：

class tuple(object):
        """
        tuple() -> empty tuple
        tuple(iterable) -> tuple initialized from iterable's items
        
        If the argument is a tuple, the return value is the same object.
        """
        def count(self, value): # real signature unknown; restored from __doc__
            """ T.count(value) -> integer -- return number of occurrences of value """
            return 0
    
        def index(self, value, start=None, stop=None): # real signature unknown; restored from __doc__
            """
            T.index(value, [start, [stop]]) -> integer -- return first index of value.
            Raises ValueError if the value is not present.
            """
            return 0
    
        def __add__(self, y): # real signature unknown; restored from __doc__
            """ x.__add__(y) <==> x+y """
            pass
    
        def __contains__(self, y): # real signature unknown; restored from __doc__
            """ x.__contains__(y) <==> y in x """
            pass
    
        def __eq__(self, y): # real signature unknown; restored from __doc__
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__getitem__(y) <==> x[y] """
            pass
    
        def __getnewargs__(self, *args, **kwargs): # real signature unknown
            pass
    
        def __getslice__(self, i, j): # real signature unknown; restored from __doc__
            """
            x.__getslice__(i, j) <==> x[i:j]
                       
                       Use of negative indices is not supported.
            """
            pass
    
        def __ge__(self, y): # real signature unknown; restored from __doc__
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y): # real signature unknown; restored from __doc__
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __hash__(self): # real signature unknown; restored from __doc__
            """ x.__hash__() <==> hash(x) """
            pass
    
        def __init__(self, seq=()): # known special case of tuple.__init__
            """
            tuple() -> empty tuple
            tuple(iterable) -> tuple initialized from iterable's items
            
            If the argument is a tuple, the return value is the same object.
            # (copied from class doc)
            """
            pass
    
        def __iter__(self): # real signature unknown; restored from __doc__
            """ x.__iter__() <==> iter(x) """
            pass
    
        def __len__(self): # real signature unknown; restored from __doc__
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y): # real signature unknown; restored from __doc__
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y): # real signature unknown; restored from __doc__
            """ x.__lt__(y) <==> x<y """
            pass
    
        def __mul__(self, n): # real signature unknown; restored from __doc__
            """ x.__mul__(n) <==> x*n """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y): # real signature unknown; restored from __doc__
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __rmul__(self, n): # real signature unknown; restored from __doc__
            """ x.__rmul__(n) <==> n*x """
            pass
    
        def __sizeof__(self): # real signature unknown; restored from __doc__
            """ T.__sizeof__() -- size of T in memory, in bytes """
            pass
    
    tuple

## **七、字典** ##

如：\{'name': 'wupeiqi', 'age': 18\} 、\{'host': '2.2.2.2', 'port': 80\]\}

ps：循环时，默认循环key

每个字典都具备如下功能：

class dict(object):
        """
        dict() -> new empty dictionary
        dict(mapping) -> new dictionary initialized from a mapping object's
            (key, value) pairs
        dict(iterable) -> new dictionary initialized as if via:
            d = {}
            for k, v in iterable:
                d[k] = v
        dict(**kwargs) -> new dictionary initialized with the name=value pairs
            in the keyword argument list.  For example:  dict(one=1, two=2)
        """
    
        def clear(self): # real signature unknown; restored from __doc__
            """ 清除内容 """
            """ D.clear() -> None.  Remove all items from D. """
            pass
    
        def copy(self): # real signature unknown; restored from __doc__
            """ 浅拷贝 """
            """ D.copy() -> a shallow copy of D """
            pass
    
        @staticmethod # known case
        def fromkeys(S, v=None): # real signature unknown; restored from __doc__
            """
            dict.fromkeys(S[,v]) -> New dict with keys from S and values equal to v.
            v defaults to None.
            """
            pass
    
        def get(self, k, d=None): # real signature unknown; restored from __doc__
            """ 根据key获取值，d是默认值 """
            """ D.get(k[,d]) -> D[k] if k in D, else d.  d defaults to None. """
            pass
    
        def has_key(self, k): # real signature unknown; restored from __doc__
            """ 是否有key """
            """ D.has_key(k) -> True if D has a key k, else False """
            return False
    
        def items(self): # real signature unknown; restored from __doc__
            """ 所有项的列表形式 """
            """ D.items() -> list of D's (key, value) pairs, as 2-tuples """
            return []
    
        def iteritems(self): # real signature unknown; restored from __doc__
            """ 项可迭代 """
            """ D.iteritems() -> an iterator over the (key, value) items of D """
            pass
    
        def iterkeys(self): # real signature unknown; restored from __doc__
            """ key可迭代 """
            """ D.iterkeys() -> an iterator over the keys of D """
            pass
    
        def itervalues(self): # real signature unknown; restored from __doc__
            """ value可迭代 """
            """ D.itervalues() -> an iterator over the values of D """
            pass
    
        def keys(self): # real signature unknown; restored from __doc__
            """ 所有的key列表 """
            """ D.keys() -> list of D's keys """
            return []
    
        def pop(self, k, d=None): # real signature unknown; restored from __doc__
            """ 获取并在字典中移除 """
            """
            D.pop(k[,d]) -> v, remove specified key and return the corresponding value.
            If key is not found, d is returned if given, otherwise KeyError is raised
            """
            pass
    
        def popitem(self): # real signature unknown; restored from __doc__
            """ 获取并在字典中移除 """
            """
            D.popitem() -> (k, v), remove and return some (key, value) pair as a
            2-tuple; but raise KeyError if D is empty.
            """
            pass
    
        def setdefault(self, k, d=None): # real signature unknown; restored from __doc__
            """ 如果key不存在，则创建，如果存在，则返回已存在的值且不修改 """
            """ D.setdefault(k[,d]) -> D.get(k,d), also set D[k]=d if k not in D """
            pass
    
        def update(self, E=None, **F): # known special case of dict.update
            """ 更新
                {'name':'alex', 'age': 18000}
                [('name','sbsbsb'),]
            """
            """
            D.update([E, ]**F) -> None.  Update D from dict/iterable E and F.
            If E present and has a .keys() method, does:     for k in E: D[k] = E[k]
            If E present and lacks .keys() method, does:     for (k, v) in E: D[k] = v
            In either case, this is followed by: for k in F: D[k] = F[k]
            """
            pass
    
        def values(self): # real signature unknown; restored from __doc__
            """ 所有的值 """
            """ D.values() -> list of D's values """
            return []
    
        def viewitems(self): # real signature unknown; restored from __doc__
            """ 所有项，只是将内容保存至view对象中 """
            """ D.viewitems() -> a set-like object providing a view on D's items """
            pass
    
        def viewkeys(self): # real signature unknown; restored from __doc__
            """ D.viewkeys() -> a set-like object providing a view on D's keys """
            pass
    
        def viewvalues(self): # real signature unknown; restored from __doc__
            """ D.viewvalues() -> an object providing a view on D's values """
            pass
    
        def __cmp__(self, y): # real signature unknown; restored from __doc__
            """ x.__cmp__(y) <==> cmp(x,y) """
            pass
    
        def __contains__(self, k): # real signature unknown; restored from __doc__
            """ D.__contains__(k) -> True if D has a key k, else False """
            return False
    
        def __delitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__delitem__(y) <==> del x[y] """
            pass
    
        def __eq__(self, y): # real signature unknown; restored from __doc__
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __getitem__(self, y): # real signature unknown; restored from __doc__
            """ x.__getitem__(y) <==> x[y] """
            pass
    
        def __ge__(self, y): # real signature unknown; restored from __doc__
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y): # real signature unknown; restored from __doc__
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __init__(self, seq=None, **kwargs): # known special case of dict.__init__
            """
            dict() -> new empty dictionary
            dict(mapping) -> new dictionary initialized from a mapping object's
                (key, value) pairs
            dict(iterable) -> new dictionary initialized as if via:
                d = {}
                for k, v in iterable:
                    d[k] = v
            dict(**kwargs) -> new dictionary initialized with the name=value pairs
                in the keyword argument list.  For example:  dict(one=1, two=2)
            # (copied from class doc)
            """
            pass
    
        def __iter__(self): # real signature unknown; restored from __doc__
            """ x.__iter__() <==> iter(x) """
            pass
    
        def __len__(self): # real signature unknown; restored from __doc__
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y): # real signature unknown; restored from __doc__
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y): # real signature unknown; restored from __doc__
            """ x.__lt__(y) <==> x<y """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y): # real signature unknown; restored from __doc__
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __setitem__(self, i, y): # real signature unknown; restored from __doc__
            """ x.__setitem__(i, y) <==> x[i]=y """
            pass
    
        def __sizeof__(self): # real signature unknown; restored from __doc__
            """ D.__sizeof__() -> size of D in memory, in bytes """
            pass
    
        __hash__ = None

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> </td> 
   <td> <p><code>练习：元素分类</code></p> <p><code>有如下值集合 [</code><code>11</code><code>,</code><code>22</code><code>,</code><code>33</code><code>,</code><code>44</code><code>,</code><code>55</code><code>,</code><code>66</code><code>,</code><code>77</code><code>,</code><code>88</code><code>,</code><code>99</code><code>,</code><code>90.</code><code>..]，将所有大于&nbsp;</code><code>66</code>&nbsp;<code>的值保存至字典的第一个key中，将小于&nbsp;</code><code>66</code>&nbsp;<code>的值保存至第二个key的值中。</code></p> <p><code>即： { </code><code>'k1'</code><code>: 大于</code><code>66</code>&nbsp;<code>,&nbsp;</code><code>'k2'</code><code>: 小于</code><code>66</code><code>}</code></p> </td> 
  </tr> 
 </tbody> 
</table>

## ** 八、set集合** ##

set是一个无序且不重复的元素集合

class set(object):
        """
        set() -> new empty set object
        set(iterable) -> new set object
        
        Build an unordered collection of unique elements.
        """
        def add(self, *args, **kwargs): # real signature unknown
            """ 添加 """
            """
            Add an element to a set.
            
            This has no effect if the element is already present.
            """
            pass
    
        def clear(self, *args, **kwargs): # real signature unknown
            """ Remove all elements from this set. """
            pass
    
        def copy(self, *args, **kwargs): # real signature unknown
            """ Return a shallow copy of a set. """
            pass
    
        def difference(self, *args, **kwargs): # real signature unknown
            """
            Return the difference of two or more sets as a new set.
            
            (i.e. all elements that are in this set but not the others.)
            """
            pass
    
        def difference_update(self, *args, **kwargs): # real signature unknown
            """ 删除当前set中的所有包含在 new set 里的元素 """
            """ Remove all elements of another set from this set. """
            pass
    
        def discard(self, *args, **kwargs): # real signature unknown
            """ 移除元素 """
            """
            Remove an element from a set if it is a member.
            
            If the element is not a member, do nothing.
            """
            pass
    
        def intersection(self, *args, **kwargs): # real signature unknown
            """ 取交集，新创建一个set """
            """
            Return the intersection of two or more sets as a new set.
            
            (i.e. elements that are common to all of the sets.)
            """
            pass
    
        def intersection_update(self, *args, **kwargs): # real signature unknown
            """ 取交集，修改原来set """
            """ Update a set with the intersection of itself and another. """
            pass
    
        def isdisjoint(self, *args, **kwargs): # real signature unknown
            """ 如果没有交集，返回true  """
            """ Return True if two sets have a null intersection. """
            pass
    
        def issubset(self, *args, **kwargs): # real signature unknown
            """ 是否是子集 """
            """ Report whether another set contains this set. """
            pass
    
        def issuperset(self, *args, **kwargs): # real signature unknown
            """ 是否是父集 """
            """ Report whether this set contains another set. """
            pass
    
        def pop(self, *args, **kwargs): # real signature unknown
            """ 移除 """
            """
            Remove and return an arbitrary set element.
            Raises KeyError if the set is empty.
            """
            pass
    
        def remove(self, *args, **kwargs): # real signature unknown
            """ 移除 """
            """
            Remove an element from a set; it must be a member.
            
            If the element is not a member, raise a KeyError.
            """
            pass
    
        def symmetric_difference(self, *args, **kwargs): # real signature unknown
            """ 差集，创建新对象"""
            """
            Return the symmetric difference of two sets as a new set.
            
            (i.e. all elements that are in exactly one of the sets.)
            """
            pass
    
        def symmetric_difference_update(self, *args, **kwargs): # real signature unknown
            """ 差集，改变原来 """
            """ Update a set with the symmetric difference of itself and another. """
            pass
    
        def union(self, *args, **kwargs): # real signature unknown
            """ 并集 """
            """
            Return the union of sets as a new set.
            
            (i.e. all elements that are in either set.)
            """
            pass
    
        def update(self, *args, **kwargs): # real signature unknown
            """ 更新 """
            """ Update a set with the union of itself and others. """
            pass
    
        def __and__(self, y): # real signature unknown; restored from __doc__
            """ x.__and__(y) <==> x&y """
            pass
    
        def __cmp__(self, y): # real signature unknown; restored from __doc__
            """ x.__cmp__(y) <==> cmp(x,y) """
            pass
    
        def __contains__(self, y): # real signature unknown; restored from __doc__
            """ x.__contains__(y) <==> y in x. """
            pass
    
        def __eq__(self, y): # real signature unknown; restored from __doc__
            """ x.__eq__(y) <==> x==y """
            pass
    
        def __getattribute__(self, name): # real signature unknown; restored from __doc__
            """ x.__getattribute__('name') <==> x.name """
            pass
    
        def __ge__(self, y): # real signature unknown; restored from __doc__
            """ x.__ge__(y) <==> x>=y """
            pass
    
        def __gt__(self, y): # real signature unknown; restored from __doc__
            """ x.__gt__(y) <==> x>y """
            pass
    
        def __iand__(self, y): # real signature unknown; restored from __doc__
            """ x.__iand__(y) <==> x&=y """
            pass
    
        def __init__(self, seq=()): # known special case of set.__init__
            """
            set() -> new empty set object
            set(iterable) -> new set object
            
            Build an unordered collection of unique elements.
            # (copied from class doc)
            """
            pass
    
        def __ior__(self, y): # real signature unknown; restored from __doc__
            """ x.__ior__(y) <==> x|=y """
            pass
    
        def __isub__(self, y): # real signature unknown; restored from __doc__
            """ x.__isub__(y) <==> x-=y """
            pass
    
        def __iter__(self): # real signature unknown; restored from __doc__
            """ x.__iter__() <==> iter(x) """
            pass
    
        def __ixor__(self, y): # real signature unknown; restored from __doc__
            """ x.__ixor__(y) <==> x^=y """
            pass
    
        def __len__(self): # real signature unknown; restored from __doc__
            """ x.__len__() <==> len(x) """
            pass
    
        def __le__(self, y): # real signature unknown; restored from __doc__
            """ x.__le__(y) <==> x<=y """
            pass
    
        def __lt__(self, y): # real signature unknown; restored from __doc__
            """ x.__lt__(y) <==> x<y """
            pass
    
        @staticmethod # known case of __new__
        def __new__(S, *more): # real signature unknown; restored from __doc__
            """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
            pass
    
        def __ne__(self, y): # real signature unknown; restored from __doc__
            """ x.__ne__(y) <==> x!=y """
            pass
    
        def __or__(self, y): # real signature unknown; restored from __doc__
            """ x.__or__(y) <==> x|y """
            pass
    
        def __rand__(self, y): # real signature unknown; restored from __doc__
            """ x.__rand__(y) <==> y&x """
            pass
    
        def __reduce__(self, *args, **kwargs): # real signature unknown
            """ Return state information for pickling. """
            pass
    
        def __repr__(self): # real signature unknown; restored from __doc__
            """ x.__repr__() <==> repr(x) """
            pass
    
        def __ror__(self, y): # real signature unknown; restored from __doc__
            """ x.__ror__(y) <==> y|x """
            pass
    
        def __rsub__(self, y): # real signature unknown; restored from __doc__
            """ x.__rsub__(y) <==> y-x """
            pass
    
        def __rxor__(self, y): # real signature unknown; restored from __doc__
            """ x.__rxor__(y) <==> y^x """
            pass
    
        def __sizeof__(self): # real signature unknown; restored from __doc__
            """ S.__sizeof__() -> size of S in memory, in bytes """
            pass
    
        def __sub__(self, y): # real signature unknown; restored from __doc__
            """ x.__sub__(y) <==> x-y """
            pass
    
        def __xor__(self, y): # real signature unknown; restored from __doc__
            """ x.__xor__(y) <==> x^y """
            pass
    
        __hash__ = None

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> <p>4</p> <p>5</p> <p>6</p> <p>7</p> <p>8</p> <p>9</p> <p>10</p> <p>11</p> <p>12</p> <p>13</p> <p>14</p> <p>15</p> <p>16</p> <p>17</p> <p>18</p> </td> 
   <td> <p><code>练习：寻找差异</code></p> <p><code># 数据库中原有</code></p> <p><code>old_dict&nbsp;</code><code>=</code>&nbsp;<code>{ </code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>"#1"</code><code>:{&nbsp;</code><code>'hostname'</code><code>:c1,&nbsp;</code><code>'cpu_count'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'mem_capicity'</code><code>:&nbsp;</code><code>80</code>&nbsp;<code>},</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>"#2"</code><code>:{&nbsp;</code><code>'hostname'</code><code>:c1,&nbsp;</code><code>'cpu_count'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'mem_capicity'</code><code>:&nbsp;</code><code>80</code>&nbsp;<code>}</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>"#3"</code><code>:{&nbsp;</code><code>'hostname'</code><code>:c1,&nbsp;</code><code>'cpu_count'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'mem_capicity'</code><code>:&nbsp;</code><code>80</code>&nbsp;<code>}</code></p> <p><code>}</code></p> <p>&nbsp;</p> <p><code># cmdb 新汇报的数据</code></p> <p><code>new_dict&nbsp;</code><code>=</code>&nbsp;<code>{ </code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>"#1"</code><code>:{&nbsp;</code><code>'hostname'</code><code>:c1,&nbsp;</code><code>'cpu_count'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'mem_capicity'</code><code>:&nbsp;</code><code>800</code>&nbsp;<code>},</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>"#3"</code><code>:{&nbsp;</code><code>'hostname'</code><code>:c1,&nbsp;</code><code>'cpu_count'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'mem_capicity'</code><code>:&nbsp;</code><code>80</code>&nbsp;<code>}</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>"#4"</code><code>:{&nbsp;</code><code>'hostname'</code><code>:c2,&nbsp;</code><code>'cpu_count'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'mem_capicity'</code><code>:&nbsp;</code><code>80</code>&nbsp;<code>}</code></p> <p><code>}</code></p> <p>&nbsp;</p> <p><code>需要删除：？</code></p> <p><code>需要新建：？</code></p> <p><code>需要更新：？ 注意：无需考虑内部元素是否改变，只要原来存在，新汇报也存在，就是需要更新</code></p> </td> 
  </tr> 
 </tbody> 
</table>

old_set = set(old_dict.keys())
    update_list = list(old_set.intersection(new_dict.keys()))
    
    new_list = []
    del_list = []
    
    for i in new_dict.keys():
        if i not in update_list:
            new_list.append(i)
    
    for i in old_dict.keys():
        if i not in update_list:
            del_list.append(i)
    
    print update_list,new_list,del_list

## **九、collection系列** ##

> 1、计数器（counter）
> 
> Counter是对字典类型的补充，用于追踪值的出现次数。
> 
> ps：具备字典的所有功能 + 自己的功能
> 
> <table> 
>  <tbody> 
>   <tr> 
>    <td> <p>1</p> <p>2</p> <p>3</p> </td> 
>    <td> <p><code>c&nbsp;</code><code>=</code>&nbsp;<code>Counter(</code><code>'abcdeabcdabcaba'</code><code>)</code></p> <p><code>print</code>&nbsp;<code>c</code></p> <p><code>输出：Counter({ </code><code>'a'</code><code>:&nbsp;</code><code>5</code><code>,&nbsp;</code><code>'b'</code><code>:&nbsp;</code><code>4</code><code>,&nbsp;</code><code>'c'</code><code>:&nbsp;</code><code>3</code><code>,&nbsp;</code><code>'d'</code><code>:&nbsp;</code><code>2</code><code>,&nbsp;</code><code>'e'</code><code>:&nbsp;</code><code>1</code><code>})</code></p> </td> 
>   </tr> 
>  </tbody> 
> </table>
> 
> ![ContractedBlock.gif][] Counter
> 
>     ########################################################################
>     ###  Counter
>     ########################################################################
>     
>     class Counter(dict):
>         '''Dict subclass for counting hashable items.  Sometimes called a bag
>         or multiset.  Elements are stored as dictionary keys and their counts
>         are stored as dictionary values.
>     
>         >>> c = Counter('abcdeabcdabcaba')  # count elements from a string
>     
>         >>> c.most_common(3)                # three most common elements
>         [('a', 5), ('b', 4), ('c', 3)]
>         >>> sorted(c)                       # list all unique elements
>         ['a', 'b', 'c', 'd', 'e']
>         >>> ''.join(sorted(c.elements()))   # list elements with repetitions
>         'aaaaabbbbcccdde'
>         >>> sum(c.values())                 # total of all counts
>     
>         >>> c['a']                          # count of letter 'a'
>         >>> for elem in 'shazam':           # update counts from an iterable
>         ...     c[elem] += 1                # by adding 1 to each element's count
>         >>> c['a']                          # now there are seven 'a'
>         >>> del c['b']                      # remove all 'b'
>         >>> c['b']                          # now there are zero 'b'
>     
>         >>> d = Counter('simsalabim')       # make another counter
>         >>> c.update(d)                     # add in the second counter
>         >>> c['a']                          # now there are nine 'a'
>     
>         >>> c.clear()                       # empty the counter
>         >>> c
>         Counter()
>     
>         Note:  If a count is set to zero or reduced to zero, it will remain
>         in the counter until the entry is deleted or the counter is cleared:
>     
>         >>> c = Counter('aaabbc')
>         >>> c['b'] -= 2                     # reduce the count of 'b' by two
>         >>> c.most_common()                 # 'b' is still in, but its count is zero
>         [('a', 3), ('c', 1), ('b', 0)]
>     
>         '''
>         # References:
>         #   http://en.wikipedia.org/wiki/Multiset
>         #   http://www.gnu.org/software/smalltalk/manual-base/html_node/Bag.html
>         #   http://www.demo2s.com/Tutorial/Cpp/0380__set-multiset/Catalog0380__set-multiset.htm
>         #   http://code.activestate.com/recipes/259174/
>         #   Knuth, TAOCP Vol. II section 4.6.3
>     
>         def __init__(self, iterable=None, **kwds):
>             '''Create a new, empty Counter object.  And if given, count elements
>             from an input iterable.  Or, initialize the count from another mapping
>             of elements to their counts.
>     
>             >>> c = Counter()                           # a new, empty counter
>             >>> c = Counter('gallahad')                 # a new counter from an iterable
>             >>> c = Counter({'a': 4, 'b': 2})           # a new counter from a mapping
>             >>> c = Counter(a=4, b=2)                   # a new counter from keyword args
>     
>             '''
>             super(Counter, self).__init__()
>             self.update(iterable, **kwds)
>     
>         def __missing__(self, key):
>             """ 对于不存在的元素，返回计数器为0 """
>             'The count of elements not in the Counter is zero.'
>             # Needed so that self[missing_item] does not raise KeyError
>             return 0
>     
>         def most_common(self, n=None):
>             """ 数量从大到写排列，获取前N个元素 """
>             '''List the n most common elements and their counts from the most
>             common to the least.  If n is None, then list all element counts.
>     
>             >>> Counter('abcdeabcdabcaba').most_common(3)
>             [('a', 5), ('b', 4), ('c', 3)]
>     
>             '''
>             # Emulate Bag.sortedByCount from Smalltalk
>             if n is None:
>                 return sorted(self.iteritems(), key=_itemgetter(1), reverse=True)
>             return _heapq.nlargest(n, self.iteritems(), key=_itemgetter(1))
>     
>         def elements(self):
>             """ 计数器中的所有元素，注：此处非所有元素集合，而是包含所有元素集合的迭代器 """
>             '''Iterator over elements repeating each as many times as its count.
>     
>             >>> c = Counter('ABCABC')
>             >>> sorted(c.elements())
>             ['A', 'A', 'B', 'B', 'C', 'C']
>     
>             # Knuth's example for prime factors of 1836:  2**2 * 3**3 * 17**1
>             >>> prime_factors = Counter({2: 2, 3: 3, 17: 1})
>             >>> product = 1
>             >>> for factor in prime_factors.elements():     # loop over factors
>             ...     product *= factor                       # and multiply them
>             >>> product
>     
>             Note, if an element's count has been set to zero or is a negative
>             number, elements() will ignore it.
>     
>             '''
>             # Emulate Bag.do from Smalltalk and Multiset.begin from C++.
>             return _chain.from_iterable(_starmap(_repeat, self.iteritems()))
>     
>         # Override dict methods where necessary
>     
>         @classmethod
>         def fromkeys(cls, iterable, v=None):
>             # There is no equivalent method for counters because setting v=1
>             # means that no element can have a count greater than one.
>             raise NotImplementedError(
>                 'Counter.fromkeys() is undefined.  Use Counter(iterable) instead.')
>     
>         def update(self, iterable=None, **kwds):
>             """ 更新计数器，其实就是增加；如果原来没有，则新建，如果有则加一 """
>             '''Like dict.update() but add counts instead of replacing them.
>     
>             Source can be an iterable, a dictionary, or another Counter instance.
>     
>             >>> c = Counter('which')
>             >>> c.update('witch')           # add elements from another iterable
>             >>> d = Counter('watch')
>             >>> c.update(d)                 # add elements from another counter
>             >>> c['h']                      # four 'h' in which, witch, and watch
>     
>             '''
>             # The regular dict.update() operation makes no sense here because the
>             # replace behavior results in the some of original untouched counts
>             # being mixed-in with all of the other counts for a mismash that
>             # doesn't have a straight-forward interpretation in most counting
>             # contexts.  Instead, we implement straight-addition.  Both the inputs
>             # and outputs are allowed to contain zero and negative counts.
>     
>             if iterable is not None:
>                 if isinstance(iterable, Mapping):
>                     if self:
>                         self_get = self.get
>                         for elem, count in iterable.iteritems():
>                             self[elem] = self_get(elem, 0) + count
>                     else:
>                         super(Counter, self).update(iterable) # fast path when counter is empty
>                 else:
>                     self_get = self.get
>                     for elem in iterable:
>                         self[elem] = self_get(elem, 0) + 1
>             if kwds:
>                 self.update(kwds)
>     
>         def subtract(self, iterable=None, **kwds):
>             """ 相减，原来的计数器中的每一个元素的数量减去后添加的元素的数量 """
>             '''Like dict.update() but subtracts counts instead of replacing them.
>             Counts can be reduced below zero.  Both the inputs and outputs are
>             allowed to contain zero and negative counts.
>     
>             Source can be an iterable, a dictionary, or another Counter instance.
>     
>             >>> c = Counter('which')
>             >>> c.subtract('witch')             # subtract elements from another iterable
>             >>> c.subtract(Counter('watch'))    # subtract elements from another counter
>             >>> c['h']                          # 2 in which, minus 1 in witch, minus 1 in watch
>             >>> c['w']                          # 1 in which, minus 1 in witch, minus 1 in watch
>             -1
>     
>             '''
>             if iterable is not None:
>                 self_get = self.get
>                 if isinstance(iterable, Mapping):
>                     for elem, count in iterable.items():
>                         self[elem] = self_get(elem, 0) - count
>                 else:
>                     for elem in iterable:
>                         self[elem] = self_get(elem, 0) - 1
>             if kwds:
>                 self.subtract(kwds)
>     
>         def copy(self):
>             """ 拷贝 """
>             'Return a shallow copy.'
>             return self.__class__(self)
>     
>         def __reduce__(self):
>             """ 返回一个元组（类型，元组） """
>             return self.__class__, (dict(self),)
>     
>         def __delitem__(self, elem):
>             """ 删除元素 """
>             'Like dict.__delitem__() but does not raise KeyError for missing values.'
>             if elem in self:
>                 super(Counter, self).__delitem__(elem)
>     
>         def __repr__(self):
>             if not self:
>                 return '%s()' % self.__class__.__name__
>             items = ', '.join(map('%r: %r'.__mod__, self.most_common()))
>             return '%s({%s})' % (self.__class__.__name__, items)
>     
>         # Multiset-style mathematical operations discussed in:
>         #       Knuth TAOCP Volume II section 4.6.3 exercise 19
>         #       and at http://en.wikipedia.org/wiki/Multiset
>         #
>         # Outputs guaranteed to only include positive counts.
>         #
>         # To strip negative and zero counts, add-in an empty counter:
>         #       c += Counter()
>     
>         def __add__(self, other):
>             '''Add counts from two counters.
>     
>             >>> Counter('abbb') + Counter('bcc')
>             Counter({'b': 4, 'c': 2, 'a': 1})
>     
>             '''
>             if not isinstance(other, Counter):
>                 return NotImplemented
>             result = Counter()
>             for elem, count in self.items():
>                 newcount = count + other[elem]
>                 if newcount > 0:
>                     result[elem] = newcount
>             for elem, count in other.items():
>                 if elem not in self and count > 0:
>                     result[elem] = count
>             return result
>     
>         def __sub__(self, other):
>             ''' Subtract count, but keep only results with positive counts.
>     
>             >>> Counter('abbbc') - Counter('bccd')
>             Counter({'b': 2, 'a': 1})
>     
>             '''
>             if not isinstance(other, Counter):
>                 return NotImplemented
>             result = Counter()
>             for elem, count in self.items():
>                 newcount = count - other[elem]
>                 if newcount > 0:
>                     result[elem] = newcount
>             for elem, count in other.items():
>                 if elem not in self and count < 0:
>                     result[elem] = 0 - count
>             return result
>     
>         def __or__(self, other):
>             '''Union is the maximum of value in either of the input counters.
>     
>             >>> Counter('abbb') | Counter('bcc')
>             Counter({'b': 3, 'c': 2, 'a': 1})
>     
>             '''
>             if not isinstance(other, Counter):
>                 return NotImplemented
>             result = Counter()
>             for elem, count in self.items():
>                 other_count = other[elem]
>                 newcount = other_count if count < other_count else count
>                 if newcount > 0:
>                     result[elem] = newcount
>             for elem, count in other.items():
>                 if elem not in self and count > 0:
>                     result[elem] = count
>             return result
>     
>         def __and__(self, other):
>             ''' Intersection is the minimum of corresponding counts.
>     
>             >>> Counter('abbb') & Counter('bcc')
>             Counter({'b': 1})
>     
>             '''
>             if not isinstance(other, Counter):
>                 return NotImplemented
>             result = Counter()
>             for elem, count in self.items():
>                 other_count = other[elem]
>                 newcount = count if count < other_count else other_count
>                 if newcount > 0:
>                     result[elem] = newcount
>             return result
>     
>     Counter
> 
> 2、有序字典(orderedDict )
> 
> orderdDict是对字典类型的补充，他记住了字典元素添加的顺序
> 
> ![ContractedBlock.gif][] OrderedDict
> 
>     class OrderedDict(dict):
>         'Dictionary that remembers insertion order'
>         # An inherited dict maps keys to values.
>         # The inherited dict provides __getitem__, __len__, __contains__, and get.
>         # The remaining methods are order-aware.
>         # Big-O running times for all methods are the same as regular dictionaries.
>     
>         # The internal self.__map dict maps keys to links in a doubly linked list.
>         # The circular doubly linked list starts and ends with a sentinel element.
>         # The sentinel element never gets deleted (this simplifies the algorithm).
>         # Each link is stored as a list of length three:  [PREV, NEXT, KEY].
>     
>         def __init__(self, *args, **kwds):
>             '''Initialize an ordered dictionary.  The signature is the same as
>             regular dictionaries, but keyword arguments are not recommended because
>             their insertion order is arbitrary.
>     
>             '''
>             if len(args) > 1:
>                 raise TypeError('expected at most 1 arguments, got %d' % len(args))
>             try:
>                 self.__root
>             except AttributeError:
>                 self.__root = root = []                     # sentinel node
>                 root[:] = [root, root, None]
>                 self.__map = {}
>             self.__update(*args, **kwds)
>     
>         def __setitem__(self, key, value, dict_setitem=dict.__setitem__):
>             'od.__setitem__(i, y) <==> od[i]=y'
>             # Setting a new item creates a new link at the end of the linked list,
>             # and the inherited dictionary is updated with the new key/value pair.
>             if key not in self:
>                 root = self.__root
>                 last = root[0]
>                 last[1] = root[0] = self.__map[key] = [last, root, key]
>             return dict_setitem(self, key, value)
>     
>         def __delitem__(self, key, dict_delitem=dict.__delitem__):
>             'od.__delitem__(y) <==> del od[y]'
>             # Deleting an existing item uses self.__map to find the link which gets
>             # removed by updating the links in the predecessor and successor nodes.
>             dict_delitem(self, key)
>             link_prev, link_next, _ = self.__map.pop(key)
>             link_prev[1] = link_next                        # update link_prev[NEXT]
>             link_next[0] = link_prev                        # update link_next[PREV]
>     
>         def __iter__(self):
>             'od.__iter__() <==> iter(od)'
>             # Traverse the linked list in order.
>             root = self.__root
>             curr = root[1]                                  # start at the first node
>             while curr is not root:
>                 yield curr[2]                               # yield the curr[KEY]
>                 curr = curr[1]                              # move to next node
>     
>         def __reversed__(self):
>             'od.__reversed__() <==> reversed(od)'
>             # Traverse the linked list in reverse order.
>             root = self.__root
>             curr = root[0]                                  # start at the last node
>             while curr is not root:
>                 yield curr[2]                               # yield the curr[KEY]
>                 curr = curr[0]                              # move to previous node
>     
>         def clear(self):
>             'od.clear() -> None.  Remove all items from od.'
>             root = self.__root
>             root[:] = [root, root, None]
>             self.__map.clear()
>             dict.clear(self)
>     
>         # -- the following methods do not depend on the internal structure --
>     
>         def keys(self):
>             'od.keys() -> list of keys in od'
>             return list(self)
>     
>         def values(self):
>             'od.values() -> list of values in od'
>             return [self[key] for key in self]
>     
>         def items(self):
>             'od.items() -> list of (key, value) pairs in od'
>             return [(key, self[key]) for key in self]
>     
>         def iterkeys(self):
>             'od.iterkeys() -> an iterator over the keys in od'
>             return iter(self)
>     
>         def itervalues(self):
>             'od.itervalues -> an iterator over the values in od'
>             for k in self:
>                 yield self[k]
>     
>         def iteritems(self):
>             'od.iteritems -> an iterator over the (key, value) pairs in od'
>             for k in self:
>                 yield (k, self[k])
>     
>         update = MutableMapping.update
>     
>         __update = update # let subclasses override update without breaking __init__
>     
>         __marker = object()
>     
>         def pop(self, key, default=__marker):
>             '''od.pop(k[,d]) -> v, remove specified key and return the corresponding
>             value.  If key is not found, d is returned if given, otherwise KeyError
>             is raised.
>     
>             '''
>             if key in self:
>                 result = self[key]
>                 del self[key]
>                 return result
>             if default is self.__marker:
>                 raise KeyError(key)
>             return default
>     
>         def setdefault(self, key, default=None):
>             'od.setdefault(k[,d]) -> od.get(k,d), also set od[k]=d if k not in od'
>             if key in self:
>                 return self[key]
>             self[key] = default
>             return default
>     
>         def popitem(self, last=True):
>             '''od.popitem() -> (k, v), return and remove a (key, value) pair.
>             Pairs are returned in LIFO order if last is true or FIFO order if false.
>     
>             '''
>             if not self:
>                 raise KeyError('dictionary is empty')
>             key = next(reversed(self) if last else iter(self))
>             value = self.pop(key)
>             return key, value
>     
>         def __repr__(self, _repr_running={}):
>             'od.__repr__() <==> repr(od)'
>             call_key = id(self), _get_ident()
>             if call_key in _repr_running:
>                 return '...'
>             _repr_running[call_key] = 1
>             try:
>                 if not self:
>                     return '%s()' % (self.__class__.__name__,)
>                 return '%s(%r)' % (self.__class__.__name__, self.items())
>             finally:
>                 del _repr_running[call_key]
>     
>         def __reduce__(self):
>             'Return state information for pickling'
>             items = [[k, self[k]] for k in self]
>             inst_dict = vars(self).copy()
>             for k in vars(OrderedDict()):
>                 inst_dict.pop(k, None)
>             if inst_dict:
>                 return (self.__class__, (items,), inst_dict)
>             return self.__class__, (items,)
>     
>         def copy(self):
>             'od.copy() -> a shallow copy of od'
>             return self.__class__(self)
>     
>         @classmethod
>         def fromkeys(cls, iterable, value=None):
>             '''OD.fromkeys(S[, v]) -> New ordered dictionary with keys from S.
>             If not specified, the value defaults to None.
>     
>             '''
>             self = cls()
>             for key in iterable:
>                 self[key] = value
>             return self
>     
>         def __eq__(self, other):
>             '''od.__eq__(y) <==> od==y.  Comparison to another OD is order-sensitive
>             while comparison to a regular mapping is order-insensitive.
>     
>             '''
>             if isinstance(other, OrderedDict):
>                 return dict.__eq__(self, other) and all(_imap(_eq, self, other))
>             return dict.__eq__(self, other)
>     
>         def __ne__(self, other):
>             'od.__ne__(y) <==> od!=y'
>             return not self == other
>     
>         # -- the following methods support python 3.x style dictionary views --
>     
>         def viewkeys(self):
>             "od.viewkeys() -> a set-like object providing a view on od's keys"
>             return KeysView(self)
>     
>         def viewvalues(self):
>             "od.viewvalues() -> an object providing a view on od's values"
>             return ValuesView(self)
>     
>         def viewitems(self):
>             "od.viewitems() -> a set-like object providing a view on od's items"
>             return ItemsView(self)
>     
>     OrderedDict
> 
> 3、默认字典(defaultdict) 
> 
> 学前需求：
> 
> <table> 
>  <tbody> 
>   <tr> 
>    <td> <p>1</p> <p>2</p> </td> 
>    <td> <p><code>有如下值集合 [</code><code>11</code><code>,</code><code>22</code><code>,</code><code>33</code><code>,</code><code>44</code><code>,</code><code>55</code><code>,</code><code>66</code><code>,</code><code>77</code><code>,</code><code>88</code><code>,</code><code>99</code><code>,</code><code>90.</code><code>..]，将所有大于&nbsp;</code><code>66</code>&nbsp;<code>的值保存至字典的第一个key中，将小于&nbsp;</code><code>66</code>&nbsp;<code>的值保存至第二个key的值中。</code></p> <p><code>即： { </code><code>'k1'</code><code>: 大于</code><code>66</code>&nbsp;<code>,&nbsp;</code><code>'k2'</code><code>: 小于</code><code>66</code><code>}</code></p> </td> 
>   </tr> 
>  </tbody> 
> </table>
> 
>  
> 
>     values = [11, 22, 33,44,55,66,77,88,99,90]
>     
>     my_dict = {}
>     
>     for value in  values:
>         if value>66:
>             if my_dict.has_key('k1'):
>                 my_dict['k1'].append(value)
>             else:
>                 my_dict['k1'] = [value]
>         else:
>             if my_dict.has_key('k2'):
>                 my_dict['k2'].append(value)
>             else:
>                 my_dict['k2'] = [value]
> 
> ![ContractedBlock.gif][] defaultdict字典解决方法
> 
>     from collections import defaultdict
>     
>     values = [11, 22, 33,44,55,66,77,88,99,90]
>     
>     my_dict = defaultdict(list)
>     
>     for value in  values:
>         if value>66:
>             my_dict['k1'].append(value)
>         else:
>             my_dict['k2'].append(value)
>     
>     defaultdict字典解决方法
> 
> defaultdict是对字典的类型的补充，他默认给字典的值设置了一个类型。
> 
> ![ContractedBlock.gif][] defaultdict
> 
>     class defaultdict(dict):
>         """
>         defaultdict(default_factory[, ...]) --> dict with default factory
>         
>         The default factory is called without arguments to produce
>         a new value when a key is not present, in __getitem__ only.
>         A defaultdict compares equal to a dict with the same items.
>         All remaining arguments are treated the same as if they were
>         passed to the dict constructor, including keyword arguments.
>         """
>         def copy(self): # real signature unknown; restored from __doc__
>             """ D.copy() -> a shallow copy of D. """
>             pass
>     
>         def __copy__(self, *args, **kwargs): # real signature unknown
>             """ D.copy() -> a shallow copy of D. """
>             pass
>     
>         def __getattribute__(self, name): # real signature unknown; restored from __doc__
>             """ x.__getattribute__('name') <==> x.name """
>             pass
>     
>         def __init__(self, default_factory=None, **kwargs): # known case of _collections.defaultdict.__init__
>             """
>             defaultdict(default_factory[, ...]) --> dict with default factory
>             
>             The default factory is called without arguments to produce
>             a new value when a key is not present, in __getitem__ only.
>             A defaultdict compares equal to a dict with the same items.
>             All remaining arguments are treated the same as if they were
>             passed to the dict constructor, including keyword arguments.
>             
>             # (copied from class doc)
>             """
>             pass
>     
>         def __missing__(self, key): # real signature unknown; restored from __doc__
>             """
>             __missing__(key) # Called by __getitem__ for missing key; pseudo-code:
>               if self.default_factory is None: raise KeyError((key,))
>               self[key] = value = self.default_factory()
>               return value
>             """
>             pass
>     
>         def __reduce__(self, *args, **kwargs): # real signature unknown
>             """ Return state information for pickling. """
>             pass
>     
>         def __repr__(self): # real signature unknown; restored from __doc__
>             """ x.__repr__() <==> repr(x) """
>             pass
>     
>         default_factory = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
>         """Factory for default value called by __missing__()."""
> 
> 4、可命名元组(namedtuple) 
> 
> 根据nametuple可以创建一个包含tuple所有功能以及其他功能的类型。
> 
> <table> 
>  <tbody> 
>   <tr> 
>    <td> <p>1</p> <p>2</p> <p>3</p> </td> 
>    <td> <p><code>import</code>&nbsp;<code>collections</code></p> <p>&nbsp;</p> <p><code>Mytuple&nbsp;</code><code>=</code>&nbsp;<code>collections.namedtuple(</code><code>'Mytuple'</code><code>,[</code><code>'x'</code><code>,&nbsp;</code><code>'y'</code><code>,&nbsp;</code><code>'z'</code><code>])</code></p> </td> 
>   </tr> 
>  </tbody> 
> </table>
> 
> ![ContractedBlock.gif][] Mytuple
> 
>     class Mytuple(__builtin__.tuple)
>      |  Mytuple(x, y)
>      |  
>      |  Method resolution order:
>      |      Mytuple
>      |      __builtin__.tuple
>      |      __builtin__.object
>      |  
>      |  Methods defined here:
>      |  
>      |  __getnewargs__(self)
>      |      Return self as a plain tuple.  Used by copy and pickle.
>      |  
>      |  __getstate__(self)
>      |      Exclude the OrderedDict from pickling
>      |  
>      |  __repr__(self)
>      |      Return a nicely formatted representation string
>      |  
>      |  _asdict(self)
>      |      Return a new OrderedDict which maps field names to their values
>      |  
>      |  _replace(_self, **kwds)
>      |      Return a new Mytuple object replacing specified fields with new values
>      |  
>      |  ----------------------------------------------------------------------
>      |  Class methods defined here:
>      |  
>      |  _make(cls, iterable, new=<built-in method __new__ of type object>, len=<built-in function len>) from __builtin__.type
>      |      Make a new Mytuple object from a sequence or iterable
>      |  
>      |  ----------------------------------------------------------------------
>      |  Static methods defined here:
>      |  
>      |  __new__(_cls, x, y)
>      |      Create new instance of Mytuple(x, y)
>      |  
>      |  ----------------------------------------------------------------------
>      |  Data descriptors defined here:
>      |  
>      |  __dict__
>      |      Return a new OrderedDict which maps field names to their values
>      |  
>      |  x
>      |      Alias for field number 0
>      |  
>      |  y
>      |      Alias for field number 1
>      |  
>      |  ----------------------------------------------------------------------
>      |  Data and other attributes defined here:
>      |  
>      |  _fields = ('x', 'y')
>      |  
>      |  ----------------------------------------------------------------------
>      |  Methods inherited from __builtin__.tuple:
>      |  
>      |  __add__(...)
>      |      x.__add__(y) <==> x+y
>      |  
>      |  __contains__(...)
>      |      x.__contains__(y) <==> y in x
>      |  
>      |  __eq__(...)
>      |      x.__eq__(y) <==> x==y
>      |  
>      |  __ge__(...)
>      |      x.__ge__(y) <==> x>=y
>      |  
>      |  __getattribute__(...)
>      |      x.__getattribute__('name') <==> x.name
>      |  
>      |  __getitem__(...)
>      |      x.__getitem__(y) <==> x[y]
>      |  
>      |  __getslice__(...)
>      |      x.__getslice__(i, j) <==> x[i:j]
>      |      
>      |      Use of negative indices is not supported.
>      |  
>      |  __gt__(...)
>      |      x.__gt__(y) <==> x>y
>      |  
>      |  __hash__(...)
>      |      x.__hash__() <==> hash(x)
>      |  
>      |  __iter__(...)
>      |      x.__iter__() <==> iter(x)
>      |  
>      |  __le__(...)
>      |      x.__le__(y) <==> x<=y
>      |  
>      |  __len__(...)
>      |      x.__len__() <==> len(x)
>      |  
>      |  __lt__(...)
>      |      x.__lt__(y) <==> x<y
>      |  
>      |  __mul__(...)
>      |      x.__mul__(n) <==> x*n
>      |  
>      |  __ne__(...)
>      |      x.__ne__(y) <==> x!=y
>      |  
>      |  __rmul__(...)
>      |      x.__rmul__(n) <==> n*x
>      |  
>      |  __sizeof__(...)
>      |      T.__sizeof__() -- size of T in memory, in bytes
>      |  
>      |  count(...)
>      |      T.count(value) -> integer -- return number of occurrences of value
>      |  
>      |  index(...)
>      |      T.index(value, [start, [stop]]) -> integer -- return first index of value.
>      |      Raises ValueError if the value is not present.
> 
>

> 5、双向队列(deque)
> 
> 一个线程安全的双向队列
> 
> ![ContractedBlock.gif][] deque
> 
>     class deque(object):
>         """
>         deque([iterable[, maxlen]]) --> deque object
>         
>         Build an ordered collection with optimized access from its endpoints.
>         """
>         def append(self, *args, **kwargs): # real signature unknown
>             """ Add an element to the right side of the deque. """
>             pass
>     
>         def appendleft(self, *args, **kwargs): # real signature unknown
>             """ Add an element to the left side of the deque. """
>             pass
>     
>         def clear(self, *args, **kwargs): # real signature unknown
>             """ Remove all elements from the deque. """
>             pass
>     
>         def count(self, value): # real signature unknown; restored from __doc__
>             """ D.count(value) -> integer -- return number of occurrences of value """
>             return 0
>     
>         def extend(self, *args, **kwargs): # real signature unknown
>             """ Extend the right side of the deque with elements from the iterable """
>             pass
>     
>         def extendleft(self, *args, **kwargs): # real signature unknown
>             """ Extend the left side of the deque with elements from the iterable """
>             pass
>     
>         def pop(self, *args, **kwargs): # real signature unknown
>             """ Remove and return the rightmost element. """
>             pass
>     
>         def popleft(self, *args, **kwargs): # real signature unknown
>             """ Remove and return the leftmost element. """
>             pass
>     
>         def remove(self, value): # real signature unknown; restored from __doc__
>             """ D.remove(value) -- remove first occurrence of value. """
>             pass
>     
>         def reverse(self): # real signature unknown; restored from __doc__
>             """ D.reverse() -- reverse *IN PLACE* """
>             pass
>     
>         def rotate(self, *args, **kwargs): # real signature unknown
>             """ Rotate the deque n steps to the right (default n=1).  If n is negative, rotates left. """
>             pass
>     
>         def __copy__(self, *args, **kwargs): # real signature unknown
>             """ Return a shallow copy of a deque. """
>             pass
>     
>         def __delitem__(self, y): # real signature unknown; restored from __doc__
>             """ x.__delitem__(y) <==> del x[y] """
>             pass
>     
>         def __eq__(self, y): # real signature unknown; restored from __doc__
>             """ x.__eq__(y) <==> x==y """
>             pass
>     
>         def __getattribute__(self, name): # real signature unknown; restored from __doc__
>             """ x.__getattribute__('name') <==> x.name """
>             pass
>     
>         def __getitem__(self, y): # real signature unknown; restored from __doc__
>             """ x.__getitem__(y) <==> x[y] """
>             pass
>     
>         def __ge__(self, y): # real signature unknown; restored from __doc__
>             """ x.__ge__(y) <==> x>=y """
>             pass
>     
>         def __gt__(self, y): # real signature unknown; restored from __doc__
>             """ x.__gt__(y) <==> x>y """
>             pass
>     
>         def __iadd__(self, y): # real signature unknown; restored from __doc__
>             """ x.__iadd__(y) <==> x+=y """
>             pass
>     
>         def __init__(self, iterable=(), maxlen=None): # known case of _collections.deque.__init__
>             """
>             deque([iterable[, maxlen]]) --> deque object
>             
>             Build an ordered collection with optimized access from its endpoints.
>             # (copied from class doc)
>             """
>             pass
>     
>         def __iter__(self): # real signature unknown; restored from __doc__
>             """ x.__iter__() <==> iter(x) """
>             pass
>     
>         def __len__(self): # real signature unknown; restored from __doc__
>             """ x.__len__() <==> len(x) """
>             pass
>     
>         def __le__(self, y): # real signature unknown; restored from __doc__
>             """ x.__le__(y) <==> x<=y """
>             pass
>     
>         def __lt__(self, y): # real signature unknown; restored from __doc__
>             """ x.__lt__(y) <==> x<y """
>             pass
>     
>         @staticmethod # known case of __new__
>         def __new__(S, *more): # real signature unknown; restored from __doc__
>             """ T.__new__(S, ...) -> a new object with type S, a subtype of T """
>             pass
>     
>         def __ne__(self, y): # real signature unknown; restored from __doc__
>             """ x.__ne__(y) <==> x!=y """
>             pass
>     
>         def __reduce__(self, *args, **kwargs): # real signature unknown
>             """ Return state information for pickling. """
>             pass
>     
>         def __repr__(self): # real signature unknown; restored from __doc__
>             """ x.__repr__() <==> repr(x) """
>             pass
>     
>         def __reversed__(self): # real signature unknown; restored from __doc__
>             """ D.__reversed__() -- return a reverse iterator over the deque """
>             pass
>     
>         def __setitem__(self, i, y): # real signature unknown; restored from __doc__
>             """ x.__setitem__(i, y) <==> x[i]=y """
>             pass
>     
>         def __sizeof__(self): # real signature unknown; restored from __doc__
>             """ D.__sizeof__() -- size of D in memory, in bytes """
>             pass
>     
>         maxlen = property(lambda self: object(), lambda self, v: None, lambda self: None)  # default
>         """maximum size of a deque or None if unbounded"""
>     
>     
>         __hash__ = None
> 
> 注：既然有双向队列，也有单项队列（先进先出 FIFO ）
> 
> ![ContractedBlock.gif][] Queue.Queue
> 
>     class Queue:
>         """Create a queue object with a given maximum size.
>     
>         If maxsize is <= 0, the queue size is infinite.
>         """
>         def __init__(self, maxsize=0):
>             self.maxsize = maxsize
>             self._init(maxsize)
>             # mutex must be held whenever the queue is mutating.  All methods
>             # that acquire mutex must release it before returning.  mutex
>             # is shared between the three conditions, so acquiring and
>             # releasing the conditions also acquires and releases mutex.
>             self.mutex = _threading.Lock()
>             # Notify not_empty whenever an item is added to the queue; a
>             # thread waiting to get is notified then.
>             self.not_empty = _threading.Condition(self.mutex)
>             # Notify not_full whenever an item is removed from the queue;
>             # a thread waiting to put is notified then.
>             self.not_full = _threading.Condition(self.mutex)
>             # Notify all_tasks_done whenever the number of unfinished tasks
>             # drops to zero; thread waiting to join() is notified to resume
>             self.all_tasks_done = _threading.Condition(self.mutex)
>             self.unfinished_tasks = 0
>     
>         def task_done(self):
>             """Indicate that a formerly enqueued task is complete.
>     
>             Used by Queue consumer threads.  For each get() used to fetch a task,
>             a subsequent call to task_done() tells the queue that the processing
>             on the task is complete.
>     
>             If a join() is currently blocking, it will resume when all items
>             have been processed (meaning that a task_done() call was received
>             for every item that had been put() into the queue).
>     
>             Raises a ValueError if called more times than there were items
>             placed in the queue.
>             """
>             self.all_tasks_done.acquire()
>             try:
>                 unfinished = self.unfinished_tasks - 1
>                 if unfinished <= 0:
>                     if unfinished < 0:
>                         raise ValueError('task_done() called too many times')
>                     self.all_tasks_done.notify_all()
>                 self.unfinished_tasks = unfinished
>             finally:
>                 self.all_tasks_done.release()
>     
>         def join(self):
>             """Blocks until all items in the Queue have been gotten and processed.
>     
>             The count of unfinished tasks goes up whenever an item is added to the
>             queue. The count goes down whenever a consumer thread calls task_done()
>             to indicate the item was retrieved and all work on it is complete.
>     
>             When the count of unfinished tasks drops to zero, join() unblocks.
>             """
>             self.all_tasks_done.acquire()
>             try:
>                 while self.unfinished_tasks:
>                     self.all_tasks_done.wait()
>             finally:
>                 self.all_tasks_done.release()
>     
>         def qsize(self):
>             """Return the approximate size of the queue (not reliable!)."""
>             self.mutex.acquire()
>             n = self._qsize()
>             self.mutex.release()
>             return n
>     
>         def empty(self):
>             """Return True if the queue is empty, False otherwise (not reliable!)."""
>             self.mutex.acquire()
>             n = not self._qsize()
>             self.mutex.release()
>             return n
>     
>         def full(self):
>             """Return True if the queue is full, False otherwise (not reliable!)."""
>             self.mutex.acquire()
>             n = 0 < self.maxsize == self._qsize()
>             self.mutex.release()
>             return n
>     
>         def put(self, item, block=True, timeout=None):
>             """Put an item into the queue.
>     
>             If optional args 'block' is true and 'timeout' is None (the default),
>             block if necessary until a free slot is available. If 'timeout' is
>             a non-negative number, it blocks at most 'timeout' seconds and raises
>             the Full exception if no free slot was available within that time.
>             Otherwise ('block' is false), put an item on the queue if a free slot
>             is immediately available, else raise the Full exception ('timeout'
>             is ignored in that case).
>             """
>             self.not_full.acquire()
>             try:
>                 if self.maxsize > 0:
>                     if not block:
>                         if self._qsize() == self.maxsize:
>                             raise Full
>                     elif timeout is None:
>                         while self._qsize() == self.maxsize:
>                             self.not_full.wait()
>                     elif timeout < 0:
>                         raise ValueError("'timeout' must be a non-negative number")
>                     else:
>                         endtime = _time() + timeout
>                         while self._qsize() == self.maxsize:
>                             remaining = endtime - _time()
>                             if remaining <= 0.0:
>                                 raise Full
>                             self.not_full.wait(remaining)
>                 self._put(item)
>                 self.unfinished_tasks += 1
>                 self.not_empty.notify()
>             finally:
>                 self.not_full.release()
>     
>         def put_nowait(self, item):
>             """Put an item into the queue without blocking.
>     
>             Only enqueue the item if a free slot is immediately available.
>             Otherwise raise the Full exception.
>             """
>             return self.put(item, False)
>     
>         def get(self, block=True, timeout=None):
>             """Remove and return an item from the queue.
>     
>             If optional args 'block' is true and 'timeout' is None (the default),
>             block if necessary until an item is available. If 'timeout' is
>             a non-negative number, it blocks at most 'timeout' seconds and raises
>             the Empty exception if no item was available within that time.
>             Otherwise ('block' is false), return an item if one is immediately
>             available, else raise the Empty exception ('timeout' is ignored
>             in that case).
>             """
>             self.not_empty.acquire()
>             try:
>                 if not block:
>                     if not self._qsize():
>                         raise Empty
>                 elif timeout is None:
>                     while not self._qsize():
>                         self.not_empty.wait()
>                 elif timeout < 0:
>                     raise ValueError("'timeout' must be a non-negative number")
>                 else:
>                     endtime = _time() + timeout
>                     while not self._qsize():
>                         remaining = endtime - _time()
>                         if remaining <= 0.0:
>                             raise Empty
>                         self.not_empty.wait(remaining)
>                 item = self._get()
>                 self.not_full.notify()
>                 return item
>             finally:
>                 self.not_empty.release()
>     
>         def get_nowait(self):
>             """Remove and return an item from the queue without blocking.
>     
>             Only get an item if one is immediately available. Otherwise
>             raise the Empty exception.
>             """
>             return self.get(False)
>     
>         # Override these methods to implement other queue organizations
>         # (e.g. stack or priority queue).
>         # These will only be called with appropriate locks held
>     
>         # Initialize the queue representation
>         def _init(self, maxsize):
>             self.queue = deque()
>     
>         def _qsize(self, len=len):
>             return len(self.queue)
>     
>         # Put a new item in the queue
>         def _put(self, item):
>             self.queue.append(item)
>     
>         # Get an item from the queue
>         def _get(self):
>             return self.queue.popleft()
> 
>

# 迭代器和生成器 #

## **一、迭代器** ##

对于Python 列表的 for 循环，他的内部原理：查看下一个元素是否存在，如果存在，则取出，如果不存在，则报异常 StopIteration。（python内部对异常已处理）

## **二、生成器** ##

range不是生成器 和 xrange 是生成器

readlines不是生成器 和 xreadlines 是生成器

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> <p>4</p> </td> 
   <td> <p><code>&gt;&gt;&gt;&nbsp;</code><code>print</code>&nbsp;<code>range</code><code>(</code><code>10</code><code>)</code></p> <p><code>[</code><code>0</code><code>,&nbsp;</code><code>1</code><code>,&nbsp;</code><code>2</code><code>,&nbsp;</code><code>3</code><code>,&nbsp;</code><code>4</code><code>,&nbsp;</code><code>5</code><code>,&nbsp;</code><code>6</code><code>,&nbsp;</code><code>7</code><code>,&nbsp;</code><code>8</code><code>,&nbsp;</code><code>9</code><code>]</code></p> <p><code>&gt;&gt;&gt;&nbsp;</code><code>print</code>&nbsp;<code>xrange</code><code>(</code><code>10</code><code>)</code></p> <p><code>xrange</code><code>(</code><code>10</code><code>)</code></p> </td> 
  </tr> 
 </tbody> 
</table>

生成器内部基于yield创建，即：对于生成器只有使用时才创建，从而不避免内存浪费

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> <p>4</p> <p>5</p> <p>6</p> <p>7</p> <p>8</p> <p>9</p> <p>10</p> <p>11</p> </td> 
   <td> <p><code>练习：&lt;br&gt;有如下列表：</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>[</code><code>13</code><code>,&nbsp;</code><code>22</code><code>,&nbsp;</code><code>6</code><code>,&nbsp;</code><code>99</code><code>,&nbsp;</code><code>11</code><code>]</code></p> <p>&nbsp;</p> <p><code>请按照一下规则计算：</code></p> <p><code>13</code>&nbsp;<code>和&nbsp;</code><code>22</code>&nbsp;<code>比较，将大的值放在右侧，即：[</code><code>13</code><code>,&nbsp;</code><code>22</code><code>,&nbsp;</code><code>6</code><code>,&nbsp;</code><code>99</code><code>,&nbsp;</code><code>11</code><code>]</code></p> <p><code>22</code>&nbsp;<code>和&nbsp;</code><code>6</code>&nbsp;<code>比较，将大的值放在右侧，即：[</code><code>13</code><code>,&nbsp;</code><code>6</code><code>,&nbsp;</code><code>22</code><code>,&nbsp;</code><code>99</code><code>,&nbsp;</code><code>11</code><code>]</code></p> <p><code>22</code>&nbsp;<code>和&nbsp;</code><code>99</code>&nbsp;<code>比较，将大的值放在右侧，即：[</code><code>13</code><code>,&nbsp;</code><code>6</code><code>,&nbsp;</code><code>22</code><code>,&nbsp;</code><code>99</code><code>,&nbsp;</code><code>11</code><code>]</code></p> <p><code>99</code>&nbsp;<code>和&nbsp;</code><code>42</code>&nbsp;<code>比较，将大的值放在右侧，即：[</code><code>13</code><code>,&nbsp;</code><code>6</code><code>,&nbsp;</code><code>22</code><code>,&nbsp;</code><code>11</code><code>,&nbsp;</code><code>99</code><code>,]</code></p> <p>&nbsp;</p> <p><code>13</code>&nbsp;<code>和&nbsp;</code><code>6</code>&nbsp;<code>比较，将大的值放在右侧，即：[</code><code>6</code><code>,&nbsp;</code><code>13</code><code>,&nbsp;</code><code>22</code><code>,&nbsp;</code><code>11</code><code>,&nbsp;</code><code>99</code><code>,]</code></p> <p><code>...</code></p> </td> 
  </tr> 
 </tbody> 
</table>

li = [13, 22, 6, 99, 11]
    
    for m in range(len(li)-1):
    
        for n in range(m+1, len(li)):
            if li[m]> li[n]:
                temp = li[n]
                li[n] = li[m]
                li[m] = temp
    
    print li

## 三、深浅拷贝 ##

为什么要拷贝？

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> </td> 
   <td> <p><code>当进行修改时，想要保留原来的数据和修改后的数据</code></p> </td> 
  </tr> 
 </tbody> 
</table>

数字字符串 和 集合 在修改时的差异？ **（深浅拷贝不同的终极原因）**

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> <p>2</p> <p>3</p> </td> 
   <td> <p><code>在修改数据时：</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;</code><code>数字字符串：在内存中新建一份数据</code></p> <p><code>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code>集合：修改内存中的同一份数据</code></p> </td> 
  </tr> 
 </tbody> 
</table>

对于集合，如何保留其修改前和修改后的数据？

<table> 
 <tbody> 
  <tr> 
   <td> <p>1</p> </td> 
   <td> <p><code>在内存中拷贝一份</code></p> </td> 
  </tr> 
 </tbody> 
</table>

对于集合，如何拷贝其n层元素同时拷贝？

[https_www.cnblogs.com_wupeiqi_articles_4911365.html]: https://www.cnblogs.com/wupeiqi/articles/4911365.html
[425762-20151031133946575-1667336241.png]: /images/20220322/c38e48be43784b69b8f901f9b62319eb.png
[425762-20151031134228200-1953404420.png]: https://images2015.cnblogs.com/blog/425762/201510/425762-20151031134228200-1953404420.png
[425762-20151031134348685-1255331039.png]: https://images2015.cnblogs.com/blog/425762/201510/425762-20151031134348685-1255331039.png
[425762-20151031134548575-1768286588.png]: /images/20220322/631e349817cb49e6a11ce7f67c9d6c05.png
[ContractedBlock.gif]: /images/20220322/9b7a459df43a48c68a3386b39fc00de8.png