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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_perturbed_indices(self, tol=1e-8):
 """ Gets indices of perturbed elements of the deformation gradient, i. e. those that differ from the identity """

        indices = list(zip(*np.where(abs(self - np.eye(3)) > tol)))
        return indices