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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 start(self):
 """ Start the patch """

        self._patcher = mock.patch(target=self.target)
        MockClient = self._patcher.start()
        instance = MockClient.return_value
        instance.model.side_effect = mock.Mock(
            side_effect=self.model
        )