def METHOD_NAME():
    color = np.c_[100, 127, 128]
    delta = np.c_[0, 0, 0]
    res = colormap._lab_delta(color, color)
    res_2 = colormap._lab_delta(color, delta)
    npt.assert_equal(res, 0)
    npt.assert_equal(np.round(res_2), [206])