While starting to look at typing, I found some code we took from CPython 2.7 and was not updated. Briefly tested manually, it looks like it's working (but please check, this is my first time touching CMS in quite some time).

[stefano-maggiolo]

This change is 

[codecov]

Codecov Report

Merging #1174 (7cf9858) into master (81fb9df) will decrease coverage by 0.13%.
The diff coverage is 50.00%.

❗ Current head 7cf9858 differs from pull request most recent head 98cf097. Consider uploading reports for the commit 98cf097 to get more accurate results

@@            Coverage Diff             @@
##           master    #1174      +/-   ##
==========================================
- Coverage   63.67%   63.54%   -0.14%     
==========================================
  Files         232      232              
  Lines       17048    17042       -6     
==========================================
- Hits        10856    10830      -26     
- Misses       6192     6212      +20     

Flag	Coverage Δ
functionaltests	47.42% <37.50%> (-0.15%)	⬇️
unittests	44.14% <50.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
cms/log.py	92.30% <50.00%> (+0.71%)	⬆️
cms/service/EvaluationService.py	72.88% <0.00%> (-4.73%)	⬇️
cms/db/base.py	86.13% <0.00%> (-2.98%)	⬇️
cms/service/esoperations.py	81.25% <0.00%> (-2.78%)	⬇️
cms/db/util.py	54.07% <0.00%> (-1.49%)	⬇️
cms/grading/Job.py	88.18% <0.00%> (-1.11%)	⬇️
cms/grading/tasktypes/Batch.py	96.55% <0.00%> (-0.69%)	⬇️
cms/db/filecacher.py	77.09% <0.00%> (-0.65%)	⬇️
cms/service/ProxyService.py	67.17% <0.00%> (-0.51%)	⬇️
cms/io/rpc.py	94.21% <0.00%> (ø)
... and 7 more

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[andreyv]

As far as I can see, the upstream changes are ported correctly, and the custom code is preserved. Looks good!

[stefano-maggiolo]

Thank you Andrey!