Comment # 3 on bug 1026336 from Wolfgang Bauer

Well, the main problem here is that kdevelop5-plugins-python3 fails to build
against python 3.6.

Support has been added in 5.1 according to my knowledge, but that's still beta.
And it's probably not easy to backport that to 5.0.

I will have a look.

One thing you could try is to install kdevelop4 and kdevelop4-plugin-python, if
python2 support is ok for you.
Although there may be dependency problem with the latest python-sip...