Add test_calculate

[juraskov]

Add tests for calculate.py and minor fixes

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 62.21%. Comparing base (4bd5c1f) to head (72923b2).

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #111      +/-   ##
==========================================
+ Coverage   61.28%   62.21%   +0.92%     
==========================================
  Files          37       37              
  Lines        4213     4213              
==========================================
+ Hits         2582     2621      +39     
+ Misses       1631     1592      -39     

Flag	Coverage Δ
python-3.9	58.20% <100.00%> (+0.92%)	⬆️
python-3.9-ace	58.20% <100.00%> (+0.92%)	⬆️
python-3.9-mace	62.02% <100.00%> (+0.92%)	⬆️

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