Generation of .pyc files

[psifertex]

One area for potential improvement in startup time would be better creation of pyc files. For python > 3.8, it's possible to use PYTHONPYCACHEPREFIX to fix a location out of band that would store the created PYC files. This lets us save created pyc files in a writable location and save startup launch.

[emesare]

Related issue which this may address #6016

I believe from @plafosse's comment this would close that, I have also observed that the python plugin is 90% of the startup time.

[plafosse]

Unfortunatly not. It improves things but not hugely.