下载了相关合约数据，在界面上点击回测按钮时，出现如下提示：

Traceback (most recent call last):
File "C:\vnstudio\lib\site-packages\vnpy\app\cta_backtester\ui\widget.py", line 300, in start_backtesting
capital = float(self.capital_line.text())
TypeError: start_backtesting() takes 12 positional arguments but 13 were given

不知道是问题出在哪里，还请大佬帮忙看看？