Ubuntu

It works with the following command:

for i in $(cat ppas.list); do sudo add-apt-repository "$i"; done

The following is tested with Ubuntu 13.04 and system's Python, using Gtk bindings (PyGobject).

Here is one way a bit dirty though and it needs more investigation:

Summary

Ok, so there are several options:

• disown

You can combine disown and & to push your script to the background

$...