Uwe Brauer <oub@mat.ucm.es> writes:

> Hi
>
> I am running Ubuntu 16.04 and I installed python3.6 (which is not
> officially supported for that Ubuntu version via
> https://askubuntu.com/questions/865554/how-do-i-install-python-3-6-using-apt-get
>
> I also installed
>
> sudo -H python3.6 -m pip install jupyter
> sudo -H python3.6 -m pip install pexpect
> sudo -H python3.6 -m pip install matlab_kernel
>
>
> Now however I cannot open even simple org files, I obtain errors I attach
> and most of my keybinding and other things do not work.
>
> Any help is strongly appreciated.
>
> Regards
>

The whole transition from v2.x to v3.x for python has been a terrible
mess. Version issues are the most frustrating aspect of Python and one
reason I've never embraced the language.

Given that Ubuntu 16.04 was end of life in April 2021, my recommendation
would be to upgrade to ubuntu 21.04. That version seems to have a more
consistent Python environment (based on v3). It also has newer ciaro,
hafbuzz and other libs used by Emacs which will likely work better and
once Emacs 28.0 is released, will have the gccjit libs necessary for
native comp etc.