Python-сообщество

class A(object):

    x = 'A param'

    def foo(self):
        print 'A foo'

    def bar(self):
        print 'A bar'


class B(object):

    x = 'B param'

    def foo(self):
        print 'B foo'


class Account(A, B):

    x = 'C param'
    state = 'B'

    def foo(self):
        print 'Account foo'

    def bar(self):
        print 'Account bar'

obj = Account()
obj.foo()
obj.bar()

B foo
Account bar

    def __getattribute__(self, name):

        # get self class
        self_cls = object.__getattribute__(self, '__class__')

        # get parents classes
        parents = self_cls.mro()

        # get need state class(e.g. A, B)
        cls_name = object.__getattribute__(self, 'state')

        # find need class in parents class
        cls = (cls for cls in parents if cls.__name__.endswith(cls_name)).next()