Spotify playlists are great but I would like to be able to shuffle from a combination of them. Playlist folders do not cut it because then all combinations must

Spotify playlists are great but I would like to be able to shuffle from a combination of them. Playlist folders do not cut it because then all combinations must form a tree. So I made a shell script to create those combined playlists [1]! [1]: https://github.com/axelf4/nixos-config/blob/da60a706809847695fef7ea40e1ac07a1f94e5a0/packages/spotify-mix-playlists/spotify-mix-playlists https://github.com/axelf4/nixos-config/blob/da60a70680984769...