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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 get_frequencies_with_eigenvectors(self, q):
 """Calculate phonon frequencies and eigenvectors at a given q-point Parameters q: array_like A q-vector. shape=(3,) Returns ------- (frequencies, eigenvectors) frequencies: ndarray Phonon frequencies shape=(bands, ), dtype='double', order='C' eigenvectors: ndarray Phonon eigenvectors shape=(bands, bands), dtype='complex', order='C' """

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

        self._dynamical_matrix.set_dynamical_matrix(q)
        dm = self._dynamical_matrix.get_dynamical_matrix()
        frequencies = []
        eigvals, eigenvectors = np.linalg.eigh(dm)
        frequencies = []
        for eig in eigvals:
            if eig < 0:
                frequencies.append(-np.sqrt(-eig))
            else:
                frequencies.append(np.sqrt(eig))

        return np.array(frequencies) * self._factor, eigenvectors