mocker l'appel à __init__ d'une classe

test.py

        with patch('instapush.Instapush') as mock_save_data:
            with patch('instapush.App') as mock_save_data2:
                se = ServiceInstapush(self.token)
                se.save_data(self.trigger_id, **self.data)
            mock_save_data2.assert_called_once_with(user_token=self.token)
        mock_save_data.assert_called_once_with(appid='app_id',
                                               secret='secret')