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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 calculate_reduced_matrix_elements(fine_states, convention=1):
 r"""Calculate the reduced matrix elements for a list of fine states. This function calculates the reduced matrix elments .. math:: \langle N,L,J||T^1(r)||N',L',J'\rangle given a list of fine states. We calculate the reduced matrix elements found in [SteckRb87]_ for the \ D1 and D2 lines in rubidium. 2.99207750426 4.22698361868 """

    reduced_matrix_elements = [[reduced_matrix_element(ei, ej,
                                                       convention=convention)
                                for ej in fine_states]
                               for ei in fine_states]

    return reduced_matrix_elements