def METHOD_NAME(qdac):  # noqa
    # -----------------------------------------------------------------------
    with pytest.raises(ValueError) as error:
        qdac.ch01.dc_mode('step')
    # -----------------------------------------------------------------------
    assert "'step' is not in" in repr(error)
    assert "'fixed'" in repr(error)
    assert "'list'" in repr(error)
    assert "'sweep'" in repr(error)