问题出在 functools.py 文件中。该文件来自Python。我刚刚安装了新版本的python 2.7.5，并且此文件是错误的（我还有另一个-
python 2.7.5的旧安装，并且那里的functools.py文件是正确的）
要解决此问题，请替换它（关于python Lib fuctools.py中的第56行）：
convert = { '__lt__': [('__gt__', lambda self, other: other < self), ('__le__', lambda self, other: not other < self), ('__ge__', lambda self, other: not self < other)], '__le__': [('__ge__', lambda self, other: other <= self), ('__lt__', lambda self, other: not other <= self), ('__gt__', lambda self, other: not self <= other)], '__gt__': [('__lt__', lambda self, other: other > self), ('__ge__', lambda self, other: not other > self), ('__le__', lambda self, other: not self > other)], '__ge__': [('__le__', lambda self, other: other >= self), ('__gt__', lambda self, other: not other >= self), ('__lt__', lambda self, other: not self >= other)]}对此：
convert = { '__lt__': [('__gt__', lambda self, other: not (self < other or self == other)), ('__le__', lambda self, other: self < other or self == other), ('__ge__', lambda self, other: not self < other)], '__le__': [('__ge__', lambda self, other: not self <= other or self == other), ('__lt__', lambda self, other: self <= other and not self == other), ('__gt__', lambda self, other: not self <= other)], '__gt__': [('__lt__', lambda self, other: not (self > other or self == other)), ('__ge__', lambda self, other: self > other or self == other), ('__le__', lambda self, other: not self > other)], '__ge__': [('__le__', lambda self, other: (not self >= other) or self == other), ('__gt__', lambda self, other: self >= other and not self == other), ('__lt__', lambda self, other: not self >= other)]}另请阅读：http : //regebro.wordpress.com/2010/12/13/python-
implementing-rich-comparison-the-correct-
way/
