def METHOD_NAME(self):
    class A:
        __metaclass__ = abc.ABCMeta
    class B(object):
        counter = 0
        def __new__(cls):
            B.counter += 1
            return super(B, cls).__new__(cls)
    class C(A, B):
        pass
    self.assertEqual(B.counter, 0)
    C()
    self.assertEqual(B.counter, 1)