Fail if the magnitude of the given order exceeds either self.max_shares
        or self.max_notional.

def validate(self,
                 asset,
                 amount,
                 portfolio,
                 algo_datetime,
                 algo_current_data):
        """
        Fail if the magnitude of the given order exceeds either self.max_shares
        or self.max_notional.
        """

        if self.asset is not None and self.asset != asset:
            return

        if self.max_shares is not None and abs(amount) > self.max_shares:
            self.handle_violation(asset, amount, algo_datetime)

        current_asset_price = algo_current_data.current(asset, "price")
        order_value = amount * current_asset_price

        too_much_value = (self.max_notional is not None and
                          abs(order_value) > self.max_notional)

        if too_much_value:
            self.handle_violation(asset, amount, algo_datetime)