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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_averaged_interaction(self):
 """Return sum over phonon triplets of interaction strength See Eq.(21) of PRB 91, 094306 (2015) """


        # v[triplet, band0, band, band]
        v = self._interaction_strength
        w = self._weights_at_q
        v_sum = np.dot(w, v.sum(axis=2).sum(axis=2))
        return v_sum / np.prod(v.shape[2:])