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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 norm(self):
 """ Efficient computation of the Frobenius norm for ktensors Returns ------- norm : float Frobenius norm of the ktensor """

        N = len(self.shape)
        coef = outer(self.lmbda, self.lmbda)
        for i in range(N):
            coef = coef * dot(self.U[i].T, self.U[i])
        return np.sqrt(coef.sum())