哪位师傅可以讲解一下app\cta_strategy\backtesting.py文件里BacktestingEngine类的cross_limit_order()和cross_stop_order()函数代码逻辑
def new_bar(self, bar: BarData):
self.bar = bar
self.datetime = bar.datetime
self.cross_limit_order()
self.cross_stop_order()
self.strategy.on_bar(bar)
self.update_daily_close(bar.close_price)
