How to get a reference of the 'owner' class to which a method belongs in Python 3.X?

[Cosmia Luna]

I'm porting my existing work to Python 3.X, but...

class Foo:
    def bar(self):
        pass

mthd = Foo.bar

assert mthd.im_class is Foo # this does not work in py3k

So, how can I get a reference to Foo? This is important when writing
decorators, the only way I can think out is:

class Foo:
    def bar(self):
        'Foo' # manually declare the owner class
        pass

mthd = Foo.bar

assert mthd.__globals__[mthd.__doc__] is Foo # this works

class Child(Foo):
    def bar(self):
        'Child' # I have to override all method defined by bar but do nothing
        pass

child_mthd = Child.bar

assert child_mthd.__globals__[child_mthd.__doc__] is Child # this works

But the code above is quite ugly and abuses the __doc__. Is there any
equivalent in py3k of im_class?

Thanks,
Cosmia