Cleanup: docstrings in the lightly/data subpackage

[ChiragAgg5k]

This PR will mark completing cleanup of _image.py, lightly_subset.py and multi_view_collage.py files in the data subpackage according to issue #1689

after this _video.py, collage.py and dataset.py files will be left, which will be done in separate PRs due to their long size.

[ChiragAgg5k]

seems like tests are failing due to issues not introduced via this pr...

[guarin]

seems like tests are failing due to issues not introduced via this pr...

Hi, the tests fail because torchvision.transforms.Transform doesn't exist and your PR tries to import it.

[ChiragAgg5k]

ooohh ok got it. fixed it

[codecov]

Codecov Report

Attention: Patch coverage is 88.46154% with 3 lines in your changes missing coverage. Please review.

Project coverage is 85.31%. Comparing base (ad7230e) to head (4a1933f).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
lightly/data/_image.py	83.33%	2 Missing ⚠️
lightly/data/lightly_subset.py	87.50%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1741      +/-   ##
==========================================
+ Coverage   85.23%   85.31%   +0.08%     
==========================================
  Files         162      162              
  Lines        6730     6729       -1     
==========================================
+ Hits         5736     5741       +5     
+ Misses        994      988       -6     

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[ChiragAgg5k]

@guarin do review the pr when u can, thanks :D

[philippmwirth]

@guarin do review the pr when u can, thanks :D

Hi @ChiragAgg5k and thanks a lot for your contribution! Before I review, could you please remove the newly typed files from the list of files ignored by mypy here? Thank you!

[ChiragAgg5k]

@philippmwirth hi there, the PR does not focus on dataset.py file for now, thats why it's been ignored. Given the size of this file, it will be fixed in another PR

[ChiragAgg5k]

I tried removing files which were formatted from the ignore, and it lead to some errors. i will push the fixes soon

[ChiragAgg5k]

@philippmwirth any update?

[philippmwirth]

@philippmwirth any update?

Did you not want to push the fixes first?

[ChiragAgg5k]

@philippmwirth yup i do. but i am facing an issue here:

the tests are failing due to an error in the code itself:

[philippmwirth]

Thanks, @ChiragAgg5k, I'll take a look.

[philippmwirth]

Thank you @ChiragAgg5k for your help! I quickly fixed the typing problem you encountered.