Unsolved QWebEngine and Proprietary Codecs

[WeedMan]

Hello. I use PySide2 from my GNU\Linux distributive installed from pip.
QWebEngineView cannot play mp4 video. I get the following error:

[1:21:0909/151451.321433:ERROR:render_media_log.cc(30)] MediaEvent: MEDIA_ERROR_LOG_ENTRY {"error":"FFmpegDemuxer: no supported streams"}
[1:1:0909/151451.321671:ERROR:render_media_log.cc(30)] MediaEvent: PIPELINE_ERROR DEMUXER_ERROR_NO_SUPPORTED_STREAMS

I found it necessary to use proprietary audio and video codecs.

• How enable this codec in PySide2?
• Where i can see license this codec?
• Can i use default VLC player in QWebEngineView?