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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 image_amplitude(self, kwargs_ps, kwargs_lens, k=None):
 """ returns the image amplitudes :param kwargs_ps: :param kwargs_lens: :return: """

        amp_list = []
        for i, model in enumerate(self._point_source_list):
            if k is None or k == i:
                amp_list.append(model.image_amplitude(kwargs_ps=kwargs_ps[i], kwargs_lens=kwargs_lens, min_distance=self._min_distance,
                                                        search_window=self._search_window,
                                                        precision_limit=self._precision_limit,
                                                        num_iter_max=self._num_iter_max, x_center=self._x_center,
                                                        y_center=self._y_center))
        return amp_list