def METHOD_NAME(fit_rot_trans_transformation,
                                  u):
    u.trajectory.add_transformations(fit_rot_trans_transformation)
    u_p = pickle.loads(pickle.dumps(u))
    u.trajectory[0]
    for u_ts, u_p_ts in zip(u.trajectory[:5], u_p.trajectory[:5]):
        assert_almost_equal(u_ts.positions, u_p_ts.positions)