Product: Fedora https://bugzilla.redhat.com/show_bug.cgi?id=883478
--- Comment #4 from Mario Blättermann mario.blaettermann@gmail.com --- (In reply to comment #3)
... it is that %{__python3} doesn't exist on your machine.)
Yes, indeed. The python3-devel package contains some additional macros. Full review follows immediately.