def validate_predictivescalingmode(predictivescalingmode):
    """
    Validate PredictiveScalingMode for ScalingInstruction
    Property: ScalingInstruction.PredictiveScalingMode
    """

    VALID_PREDICTIVESCALINGMODE = ("ForecastAndScale", "ForecastOnly")

    if predictivescalingmode not in VALID_PREDICTIVESCALINGMODE:
        raise ValueError(
            "ScalingInstruction PredictiveScalingMode must be one of: %s"
            % ", ".join(VALID_PREDICTIVESCALINGMODE)  # noqa
        )
    return predictivescalingmode