I talked at FISL with the author of the python cantor interface module, and we noticed that fedora cantor is missing the python interface. It should be enough adding python2-devel to build requires to generate the interface, but then would need to correct file lists for extra files. The author contributed a patch to fix it in mageia, that should be this http://svnweb.mageia.org/packages/cauldron/cantor/current/SPECS/cantor.spec?r1=609332&r2=610975
cantor-4.12.5-3.fc20 has been submitted as an update for Fedora 20. https://admin.fedoraproject.org/updates/cantor-4.12.5-3.fc20
Apparently it does not work. I believe I was supposed to see a python icon, as in the screenshot at http://blog.filipesaraiva.info/?p=779 Looking at cantor documentation, in case a backend would not appear, I should go "Settings" -> "Configure Shortcuts..." but that causes cantor to crash. Reported upstream at https://bugs.kde.org/show_bug.cgi?id=334669
Looks like some other cantor bug. I confirmed I couldn't see python listed as a backend until I removed ~/.kde/share/config/cantorrc
I came back from FISL yesterday, and i think I was a bit too fast in opening bug reports, as I had a f20 2 weeks old (did not want to upgrade before going to the event), but after updating to latest f20 and restarting the computer just to make sure, the icon is now visible and the backend appears functional. But the crash in "Settings" -> "Configure Shortcuts..." still happens, both in rawhide and latest f20. Anyway, the actual bug report is corrected. May be required to exit and restart kde in f20 or remove cantorrc (rawhide did not need it, just updated to latest cantor and it just worked showing the new icon).
I consider this problem corrected. Because I can confirm python2 is listed (and usable in a quick test) as a backend in f21 and rawhide.