The python3-libcec-4.0.2-1 RPM requires both Python 2 and Python 3.
Except in very special circumstances, there is no need for one package
to drag in both Python stacks. Usually, this is a packaging error: for
example, a stray "/usr/bin/python" shebang in a Python 3 package can
introduce a Python 2 dependency.
Please split your package, or remove the stray dependencies.
There is a section on shebangs in the Python RPM Porting Guide 
which covers this issue.
It's ok to do this in Rawhide only, however, it would be greatly
appreciated if you could push it to Fedora 25 as well.
If anything is unclear, or if you need any kind of assistance, you can
ask on IRC (#fedora-python on Freenode), or reply here. We'll be happy
to help investigating or fixing this issue!
A patch would be very welcome
Created attachment 1256987 [details]
Patch to fix python3-libcec dragging in Python 2
the change needed to fix the issue is attached. Please review and apply.
Koji scratch build with the change: https://koji.fedoraproject.org/koji/taskinfo?taskID=18015443
libcec-4.0.2-2.fc25 has been submitted as an update to Fedora 25. https://bodhi.fedoraproject.org/updates/FEDORA-2017-9fd3bd0228
libcec-4.0.2-2.fc25 has been pushed to the Fedora 25 testing repository. If problems still persist, please make note of it in this bug report.
See https://fedoraproject.org/wiki/QA:Updates_Testing for
instructions on how to install test updates.
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2017-9fd3bd0228
This bug appears to have been reported against 'rawhide' during the Fedora 26 development cycle.
Changing version to '26'.
libcec-4.0.2-2.fc25 has been pushed to the Fedora 25 stable repository. If problems still persist, please make note of it in this bug report.