'Override to return the fill price and quantity for a stop order or None if the order can\'t be filled
at the given time.
:param broker_: The broker.
:type broker_: :class:`Broker`
:param order: The order.
:type order: :class:`pyalgotrade.broker.StopOrder`
:param bar: The current bar.
:type bar: :class:`pyalgotrade.bar.Bar`
:rtype: A :class:`FillInfo` or None if the order should not be filled.'

@abc.abstractmethod
def fillStopOrder(self, broker_, order, bar):

    raise NotImplementedError()
