环境：win10
报错信息：cv2.error: OpenCV(4.5.1) C:UsersappveyorAppDataLocalTemp1pip-req-build-memyuvq3opencvmoduleshighguisrcwindow.cpp:651: error: (-2:Unspecified error) The function is not implemented. Rebuild the library with Windows, GTK+ 2.x or Cocoa support. If you are on Ubuntu or Debian, install libgtk2.0-dev and pkg-config, then re-run cmake or configure script in function 'cvShowImage'
报错代码：
cv2.imshow("Demo", frame)
好像是版本原因，解决方案：
pip uninstall opencv-python pip install opencv-python
