https://github.com/jdek/openwith
https://github.com/moretension/duti
    duti -x mp4
        current assignment
    duti -s io.mpv avi all
    duti -s io.mpv mkv all
    duti -s io.mpv mp4 all

https://github.com/mpv-player/mpv/wiki/FAQ#How_can_I_make_mpv_the_default_application_for_opening_movie_files_on_macOS_OSX