Fix mypy 0.800 plus when prepending $PYTHONPATH to sys.path

[sumanthratna]

What does this PR do?

• makes mypy not complain about trying to use str.split on None
• fixes other mypy errors

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[codecov]

Codecov Report

Merging #5698 (9bc51f2) into master (6668ed7) will decrease coverage by 0%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #5698    +/-   ##
=======================================
- Coverage      93%     93%    -0%     
=======================================
  Files         134     134            
  Lines       10056    9916   -140     
=======================================
- Hits         9399    9236   -163     
- Misses        657     680    +23     

[Borda]

nice, but it seems that for some reason it fails in other places, mind fix it too?

[sumanthratna]

nice, but it seems that for some reason it fails in other places, mind fix it too?

Do you mean the ~31 other mypy errors? I'd be happy to fix them (I initially didn't because I didn't want the PR to become too bloated)

[sumanthratna]

nice, but it seems that for some reason it fails in other places, mind fix it too?

Do you mean the ~31 other mypy errors? I'd be happy to fix them

@Borda I have no idea why those are coming up (they should be ignored, according to setup.cfg). I'll keep thinking about this issue but for now, I think we should leave this PR as-is; what do you think?

[pep8speaks]

Hello @sumanthratna! Thanks for updating this PR.

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2021-02-01 00:25:43 UTC

[Borda]

nice, but it seems that for some reason it fails in other places, mind fix it too?

Do you mean the ~31 other mypy errors? I'd be happy to fix them

@Borda I have no idea why those are coming up (they should be ignored, according to setup.cfg). I'll keep thinking about this issue but for now, I think we should leave this PR as-is; what do you think?

yes, it is a known issue with recent 0.800 see python/mypy#8309
I have fixed it now so it shall be fine :]