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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 from_rotation_and_translation_and_time_reversal( rotation_matrix=((1, 0, 0), (0, 1, 0), (0, 0, 1)), translation_vec=(0, 0, 0), time_reversal=1, tol=0.1):
 """ Creates a symmetry operation from a rotation matrix, translation vector and time reversal operator. Args: rotation_matrix (3x3 array):
 Rotation matrix. translation_vec (3x1 array):
 Translation vector. time_reversal (int):
 Time reversal operator, +1 or -1. tol (float):
 Tolerance to determine if rotation matrix is valid. Returns: MagSymmOp object """

        symmop = SymmOp.from_rotation_and_translation(rotation_matrix=rotation_matrix,
                                                      translation_vec=translation_vec,
                                                      tol=tol)
        return MagSymmOp.from_symmop(symmop, time_reversal)