place sell order

def __placeSellOrder(self, tick):
        ''' place sell order '''
        if self.__position < 0:
            return

        share=self.__position
        order=Order(accountId=self.__strategy.accountId,
                         action=Action.SELL,
                         is_market=True,
                         symbol=self.__symbol,
                         share=-share)
        if self.__strategy.placeOrder(order):
            self.__position=0
            self.__buyPrice=0