>>> dir(object)
['__class__', '__delattr__', '__doc__', '__getattribute__',
'__hash__', '__init__', '__new__', '__reduce__', '__reduce_ex__',
'__repr__', '__setattr__', '__str__']
>>> class A(object):
...     pass
...
>>> dir(A)
['__class__', '__delattr__', '__dict__', '__doc__',
'__getattribute__', '__hash__', '__init__', '__module__', '__new__',
'__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__str__',
'__weakref__']
>>> [ attr for attr in dir(A) if attr not in dir(object) ]
['__dict__', '__module__', '__weakref__']
>>>

A只是简单地从object继承下来，结果就多了三个属性。实在不明白为什么。