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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def expects_call(self):
 """The fake must be called. .. doctest:: :hide: This is useful for when you stub out a function as opposed to a class. For example:: Traceback (most recent call last):
 AssertionError: fake:os.remove() was not called .. doctest:: :hide: """

        self._callable = ExpectedCall(self, call_name=self._name,
                                      callable=True)
        return self