Hey folks,
a while ago I've created a COPR repo [0] with Python 3.5 for f23,
I haven't had any bug reports so far, so it should be OK to use.
You can install it with:
$ dnf copr enable -y mstuchli/Python3.5
$ dnf install -y python35-python3
Then you can use the python3.5 and pip3.5 executables.
Some more information is available at [1].
Enjoy!
[0]
https://copr.fedoraproject.org/coprs/mstuchli/Python3.5/
[1]
http://synfo.github.io/2015/11/13/Python-3.5-in-Fedora/