Provide typing info

[asvetlov]

Type checking is rough, better checks require not released yet pytest 7.0 at least.

Tests are not typed to don't pollute this big enough PR.
They can be typed later.

Fixes #198

[codecov-commenter]

Codecov Report

Merging #260 (a94f91e) into master (0a3328f) will decrease coverage by 0.10%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #260      +/-   ##
==========================================
- Coverage   93.13%   93.02%   -0.11%     
==========================================
  Files           3        3              
  Lines         233      258      +25     
  Branches       33       33              
==========================================
+ Hits          217      240      +23     
- Misses         10       12       +2     
  Partials        6        6              

Impacted Files	Coverage Δ
plugin.py	92.88% <0.00%> (-0.10%)	⬇️

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[asvetlov]

The PR is green

[asvetlov]

Merged, if we require the type info -- better to add it fast, other PRs can use typing from the very beginning.

[jeremad]

That's great thank you very much. Sorry for the lack of response to your question in the first place.