def METHOD_NAME(self):
    '''
    Make sure '_weakref.proxy(...)==xyz' does not throw after '...'
    has been deleted.
    '''
    def helper_func():
        class C:
            def __eq__(self, *args, **kwargs): return True
        a = C()
        self.assertTrue(C()==3)
        x = _weakref.proxy(a)
        y = _weakref.proxy(a)
        self.assertEqual(x, y)
        keep_alive(a) #Just to keep 'a' alive up to this point.
        return x, y
    x, y = helper_func()
    gc.collect()
    self.assertRaises(ReferenceError, lambda: x==3)
    self.assertRaises(ReferenceError, lambda: x==y)