def METHOD_NAME():
    """
    test one time step with uncertainty on the spill
    checks there is non-zero motion.
    """
    pSpill = sample_sc_release(num_le, start_pos, rel_time,
                               uncertain=True)
    current = GridCurrent.from_netCDF(curr_file)
    py_current = CurrentMover(current=current)
    u_delta = run_uncertain_loop()
    _assert_move(u_delta)