我试着运行了下no_ui的脚本，在策略初始化之后触发异常：
Traceback (most recent call last):
File "C:\vnstudio\lib\site-packages\vnpy\app\cta_strategy\engine.py", line 584, in call_strategy_func
func()
File "C:\vnstudio\lib\site-packages\vnpy\app\cta_strategy\strategies\commodity.py", line 55, in on_init
self.load_bar(90)
File "C:\vnstudio\lib\site-packages\vnpy\app\cta_strategy\template.py", line 233, in load_bar
self.cta_engine.load_bar(self.vt_symbol, days, interval, callback)
File "C:\vnstudio\lib\site-packages\vnpy\app\cta_strategy\engine.py", line 539, in load_bar
bars = self.query_bar_from_rq(symbol, exchange, interval, start, end)
File "C:\vnstudio\lib\site-packages\vnpy\app\cta_strategy\engine.py", line 145, in query_bar_from_rq
data = rqdata_client.query_history(req)
File "C:\vnstudio\lib\site-packages\vnpy\trader\rqdata.py", line 136, in query_history
adjust_type="none"
File "C:\vnstudio\lib\site-packages\rqdatac\decorators.py", line 131, in wrap
return func(args, **kwargs)
File "C:\vnstudio\lib\site-packages\rqdatac\services\get_price.py", line 124, in get_price
pf = get_minbar(order_book_ids, start_date, end_date, fields, duration, market)
File "C:\vnstudio\lib\site-packages\rqdatac\services\get_price.py", line 441, in get_minbar
data = [(obid, {k: np.frombuffer(v) for k, v in d.items()}) for obid, d in data]
TypeError: 'NoneType' object is not iterable
好像是rqdata这边出了问题，请问应该怎么解决？
