Izlēmu nopublicēt savu /etc/apt/sources.list (lai nebūtu jāblandās pa pasauli, to meklējot).

#Ubuntu 20.04

deb http://lv.archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse
deb-src http://lv.archive.ubuntu.com/ubuntu/ focal main restricted universe multiverse
deb http://lv.archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse
deb-src http://lv.archive.ubuntu.com/ubuntu/ focal-updates main restricted universe multiverse

deb http://lv.archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse
deb-src http://lv.archive.ubuntu.com/ubuntu/ focal-security main restricted universe multiverse

# Backports
deb http://lv.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse
deb-src http://lv.archive.ubuntu.com/ubuntu/ focal-backports main restricted universe multiverse

# Canonical
deb http://archive.canonical.com/ubuntu focal partner
deb-src http://archive.canonical.com/ubuntu focal partner

# Spotify
# deb http://repository.spotify.com stable non-free
deb http://repository.spotify.com testing non-free

#LibreOffice
deb http://ppa.launchpad.net/libreoffice/ppa/ubuntu focal main
deb-src http://ppa.launchpad.net/libreoffice/ppa/ubuntu focal main

# Steam
deb [arch=amd64,i386] https://repo.steampowered.com/steam/ stable steam
deb-src [arch=amd64,i386] https://repo.steampowered.com/steam/ stable steam

# Mega
deb https://mega.nz/linux/MEGAsync/xUbuntu_20.04/ ./

# eParaksts
deb [arch=amd64] https://www.eparaksts.lv/files/ep3updates/debian focal eparaksts
# deb-src https://www.eparaksts.lv/files/ep3updates/debian focal eparaksts

#Cleaner
deb http://ppa.launchpad.net/gerardpuig/ppa/ubuntu focal main
deb-src http://ppa.launchpad.net/gerardpuig/ppa/ubuntu focal main

Ja trūskt atslēgas, tad komandai XXX vietā ieliec atslēgas aidī.
apt-key adv --keyserver keyserver.ubuntu.com --recv-keys XXX