我在虚拟环境中，运行以下代码来开启vnpy图形化界面：
from vnpy.event import EventEngine
from vnpy.trader.engine import MainEngine
from vnpy.trader.ui import MainWindow, create_qapp
from vnpy_ctp import CtpGateway
from vnpy_ctastrategy import CtaStrategyApp
from vnpy_ctabacktester import CtaBacktesterApp
from vnpy_datamanager import DataManagerApp
from vnpy_chartwizard import ChartWizardApp
def main():
"""Start VeighNa Trader"""
qapp = create_qapp()
event_engine = EventEngine()
main_engine = MainEngine(event_engine)
main_engine.add_app(ChartWizardApp)
main_engine.add_gateway(CtpGateway)
main_engine.add_app(CtaStrategyApp)
main_engine.add_app(CtaBacktesterApp)
main_engine.add_app(DataManagerApp)
main_window = MainWindow(main_engine, event_engine)
main_window.showMaximized()
qapp.exec()
if __name__ == "__main__":
main()报错提示：
qt.qpa.plugin: Could not find the Qt platform plugin "windows" in ""
我之前在这台电脑上以同样模式运行过图形化界面，最近忙了一个月其他事情，再尝试运行图形界面就出错了，求大神指点!
