cannot import name 'QtWidgets' from 'tank.platform.qt5'

[jackiezxt]

File "C:\Users\clamp\AppData\Roaming\Shotgun\bundle_cache\github\ue4plugins\tk-unreal\v1.2.0\engine.py", line 109, in init_qt_app
LogPython: Error: from sgtk.platform.qt5 import QtWidgets
LogPython: Error: ImportError: cannot import name 'QtWidgets' from 'tank.platform.qt5' (C:\Users\clamp\AppData\Roaming\Shotgun\vertpipe\p155c68.basic.unreal\cfg\install\core\python\tank\platform\qt5_init_.py)