deb http://deb.debian.org/debian/ stretch main contrib non-free #deb-src http://deb.debian.org/debian/ stretch main contrib non-free deb http://deb.debian.org/debian/ stretch-updates main contrib non-free #deb-src http://deb.debian.org/debian/ stretch-updates main contrib non-free deb http://security.debian.org/ stretch/updates main contrib non-free #deb-src http://security.debian.org/ stretch/updates main contrib non-free deb http://deb.debian.org/debian/ stretch-backports main contrib non-free #deb-src http://deb.debian.org/debian/ stretch-backports main contrib non-free