code: def settle(self):
          
          self.volume_long_his += self.volume_long_today
          self.volume_long_today = 0
          self.volume_long_frozen_today = 0
          self.volume_short_his += self.volume_short_today
          self.volume_short_today = 0
          self.volume_short_frozen_today = 0
docs: 收盘后的结算事件