deb http://ports.ubuntu.com/ubuntu-ports/ xenial main restricted universe
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial main restricted universe

deb http://ports.ubuntu.com/ubuntu-ports/ xenial-updates main restricted universe
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-updates main restricted universe

deb http://ports.ubuntu.com/ubuntu-ports/ xenial-backports main restricted
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-backports main restricted

deb http://ports.ubuntu.com/ubuntu-ports/ xenial-security main restricted universe multiverse
deb-src http://ports.ubuntu.com/ubuntu-ports/ xenial-security main restricted universe multiverse