Add support for Iterable auto dataset + resolve a bug for Preprocess Transforms.

[tchaton]

What does this PR do?

Fixes # (issue)

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[pep8speaks]

Hello @tchaton! Thanks for updating this PR.

• In the file flash/data/data_module.py:

Line 274:13: W503 line break before binary operator

• In the file flash/data/data_pipeline.py:

Line 189:13: W503 line break before binary operator

Comment last updated at 2021-04-19 14:17:03 UTC

[codecov]

Codecov Report

Merging #227 (86eaaaf) into master (42cc20a) will decrease coverage by 0.12%.
The diff coverage is 86.76%.

@@            Coverage Diff             @@
##           master     #227      +/-   ##
==========================================
- Coverage   86.61%   86.49%   -0.13%     
==========================================
  Files          57       57              
  Lines        2750     2829      +79     
==========================================
+ Hits         2382     2447      +65     
- Misses        368      382      +14     

Flag	Coverage Δ
unittests	86.49% <86.76%> (-0.13%)	⬇️

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

Impacted Files	Coverage Δ
flash/core/model.py	94.04% <55.55%> (-2.18%)	⬇️
flash/data/data_module.py	78.08% <64.28%> (-0.02%)	⬇️
flash/data/utils.py	95.95% <83.33%> (-0.92%)	⬇️
flash/data/data_pipeline.py	87.18% <86.36%> (-0.86%)	⬇️
flash/data/auto_dataset.py	94.23% <90.00%> (-2.02%)	⬇️
flash/data/process.py	86.74% <95.45%> (+2.32%)	⬆️
flash/core/classification.py	100.00% <100.00%> (ø)
flash/vision/classification/data.py	87.74% <100.00%> (-0.06%)	⬇️
flash/vision/detection/data.py	94.26% <100.00%> (-0.82%)	⬇️
... and 1 more

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[ethanwharris]

LGTM 😃

[ethanwharris]

Suggested change

	use_iterable_auto_dataset: bool = False
	use_iterable_auto_dataset: bool = False,