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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 omega(self, structure, n, u):
 """ Finds directional frequency contribution to the heat capacity from direction and polarization Args: structure (Structure):
 Structure to be used in directional heat capacity determination n (3x1 array-like):
 direction for Cv determination u (3x1 array-like):
 polarization direction, note that no attempt for verification of eigenvectors is made """

        l0 = np.dot(np.sum(structure.lattice.matrix, axis=0), n)
        l0 *= 1e-10 # in A
        weight = float(structure.composition.weight) * 1.66054e-27 # in kg
        vol = structure.volume * 1e-30 # in m^3
        vel = (1e9 * self[0].einsum_sequence([n, u, n, u])
               / (weight / vol)) ** 0.5
        return vel / l0