def METHOD_NAME(min_value):
    max_value = getattr(lut, attr)[1]
    if min_value > max_value:
        # force the movement of the maximum value
        max_value = min_value
        pl.slider_widgets[idx * 2 + 1].GetRepresentation().SetValue(max_value)
    setattr(lut, attr, (min_value, max_value))
    if attr == 'scalar_range':
        actor.mapper.scalar_range = getattr(lut, attr)