Traceback (most recent call last):
File "d:\vnstudio\lib\site-packages\vnpy_ctabacktester\ui\widget.py", line 512, in edit_strategy_code
file_path = self.backtester_engine.get_strategy_class_file(class_name)
File "d:\vnstudio\lib\site-packages\vnpy_ctabacktester\engine.py", line 462, in get_strategy_class_file
strategy_class = self.classes[class_name]
KeyError: ''