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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_modulations(self, dimension, phonon_modes, delta_q=None, derivative_order=None, nac_q_direction=None):
 """Generate atomic displacements of phonon modes. The design of this feature is not very satisfactory, and thus API. Therefore it should be reconsidered someday in the fugure. Parameters dimension : array_like Supercell dimension with respect to the primitive cell. dtype='intc', shape=(3, ), (3, 3), (9, ) phonon_modes : list of phonon mode settings Each element of the outer list gives one phonon mode information: [q-point, band index (int), amplitude (float), phase (float)] In each list of the phonon mode information, the first element is a list that represents q-point in reduced coordinates. The second, third, and fourth elements show the band index starting with 0, amplitude, and phase factor, respectively. """

        if self._dynamical_matrix is None:
            msg = ("Dynamical matrix has not yet built.")
            raise RuntimeError(msg)

        self._modulation = Modulation(self._dynamical_matrix,
                                      dimension,
                                      phonon_modes,
                                      delta_q=delta_q,
                                      derivative_order=derivative_order,
                                      nac_q_direction=nac_q_direction,
                                      factor=self._factor)
        self._modulation.run()