Code review comment for lp:~darkxst/ubuntu-release-upgrader/gnome-session-inhibit

The release upgrade process downloads a tarball of the release-upgrader from the archive for the target release e.g. http://archive.ubuntu.com/ubuntu/dists/xenial/main/dist-upgrader-all/current/xeinal.tar.gz then extracts it to a directory in /tmp/ and then runs xenial in that temporary directory. You could test it by either starting an upgrade, choosing to quit, and then make changes in /tmp/$tmpdir/DistUpgradeQuirks.py or build the package and manually extract dist-upgrader_$vernum.tar.gz.