[FEATURE REQUEST] Create a Mix object to parse a YouTube Mix/Radio

[Tickloop]

Is your feature request related to a problem? Please describe.

On YouTube there are three kinds of objects related to videos: videos, playlists, and mixes (or radios). Currently there is support for Playlists and Videos but not mixes. A link like: https://www.youtube.com/watch?v=mNEUkkoUoIA&list=RDmNEUkkoUoIA&start_radio=1 can't be parsed by either.

Describe the solution you'd like

A new class called Mix (flexible on naming) that can parse a url like: https://www.youtube.com/watch?v=mNEUkkoUoIA&list=RDmNEUkkoUoIA&start_radio=1

Describe alternatives you've considered

I have tried reformatting the link to resemble a playlist:
From: https://www.youtube.com/watch?v=mNEUkkoUoIA&list=RDmNEUkkoUoIA&start_radio=1
To: https://www.youtube.com/watch?v=mNEUkkoUoIA&list=RDmNEUkkoUoIA
and creating a Playlist object but that doesn't work

Additional context

PS: I have a basic solution, but it doesn't work with infinite scroll that YouTube mix's work on. YouTube mix will keep playing songs for infinity. We can't keep downloading them all though. Need to create a mechanism to pull more as needed.

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