通过
cta_engine.add_strategy(class_name='Test_1', strategy_name='DoubleMaStrategy', vt_symbol='ni2006.SHFE', setting={'class_name':'DoubleMaStrategy', 'fast_window':10,'slow_window':20})
添加策略的时候,提示创建策略失败,找不到策略类,请问策略类是什么?只能通过编辑cta_strategy_setting.json文件来添加策略吗?谢谢