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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 set_permutation_symmetry(force_constants):
 """Enforce permutation symmetry to force cosntants by Phi_ij_ab = Phi_ji_ba i, j: atom index a, b: Cartesian axis index This is not necessary for harmonic phonon calculation because this condition is imposed when making dynamical matrix Hermite in dynamical_matrix.py. """


    fc_copy = force_constants.copy()
    for i in range(force_constants.shape[0]):
        for j in range(force_constants.shape[1]):
            force_constants[i, j] = (force_constants[i, j] +
                                     fc_copy[j, i].T) / 2