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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 point_source_list(self, kwargs_ps, kwargs_lens, k=None):
 """ returns the coordinates and amplitudes of all point sources in a single array :param kwargs_ps: :param kwargs_lens: :return: """

        ra_list, dec_list = self.image_position(kwargs_ps, kwargs_lens, k=k)
        amp_list = self.image_amplitude(kwargs_ps, kwargs_lens)
        ra_array, dec_array, amp_array = [], [], []
        for i, ra in enumerate(ra_list):
            for j in range(len(ra)):
                ra_array.append(ra_list[i][j])
                dec_array.append(dec_list[i][j])
                amp_array.append(amp_list[i][j])
        return ra_array, dec_array, amp_array