Comment # 42 on bug 920937 from Christian Boltz

(In reply to Ian Powell from comment #41)
> ooops...  python-cups was already installed, can't find a python3-cups in
> Tumbleweed repos to install

Indeed, there's no python3 version of this package yet (I should have checked
before writing about it ;-)  python-cups only contains a python module for
python 2.7, and exactly that seems to be the problem.

/usr/share/dbus-1/services/org.fedoraproject.Config.Printing.service has
Exec=/usr/bin/scp-dbus-service and that finally calls 
/usr/share/system-config-printer/scp-dbus-service.py which has a
/usr/bin/python3 shebang line. I wouldn't be surprised if changing this line to
/usr/bin/python (without "3") would work around the problem (please test!).

The correct solution is obviously to provide a python3-cups package and to
change the dependencies in the packages that currently require python-cups.

That said, I'll pass this bug back to Johannes ;-)

In exchange for the free debugging, I hope you can help me with testing an
AppArmor profile for cups when it's ready ;-) Ubuntu has a profile we can
steal, but I want to test it myself before pushing it out to more people. Oh,
and if you want to learn something about AppArmor, just catch me at oSC15 ;-)