Use inspect.getsourcelines to get code

[androids-electric-sheep]

Fixing the bug outstanding in #1234. All credit to the original author as this is just rounding out that change

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (6310841) 95.14% compared to head (98a6e4b) 95.04%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1550      +/-   ##
==========================================
- Coverage   95.14%   95.04%   -0.11%     
==========================================
  Files          44       44              
  Lines        7562     7548      -14     
==========================================
- Hits         7195     7174      -21     
- Misses        367      374       +7     

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[fcharras]

Thanks for the PR @androids-electric-sheep , is it reasonable to say that there might still be differences in the code that is returned ? then shipping this into a new version might void the cache users built with a previous version. @tomMoral what is joblib policy on this ?