How to check if a bound method is the same as unbound

Question

I want to check (in my tests) that a method of object is the same as a method of a given class.

class Cls:
    def foo(self):
        pass

obj = Cls()
assert obj.foo == Cls.foo  # assert will fail

Which operation can be used instead of obj.foo == Cls.foo to produce True if the bound method is the same as unbound (except for 'boundness')?

Answer 1

On Python 2.7.x :

>>> Cls.foo.__func__ is obj.foo.__func__
True

Answer 2

In Python 3:

>>> class Cls:
...     def foo(self):
...         pass
... 
>>> obj = Cls()
>>> obj.foo
<bound method Cls.foo of <__main__.Cls object at 0x101d8f588>>
>>> dir(obj.foo)
['__call__', '__class__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__func__', '__ge__', '__get__', '__getattribute__', '__gt__', '__hash__', '__init__', '__le__', '__lt__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__self__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']
>>> obj.foo.__func__
<function Cls.foo at 0x101d92400>
>>> obj.foo.__func__ is Cls.foo
True

Looking through the dir() of an object is an easy way to explore and look for potentially useful attributes.