Fix MNIST 503 error by changing URL to AWS S3

[akihironitta]

What does this PR do?

Fixes #632.

There are two options to fix the issue:

1. Change URL from yann.lecun.com to the updated one (Fix MNIST download for minor release pytorch/vision#3559), (which is this PR)
2. Upgrade the minimum version of torchvision to 0.9.1, i.e. torchvision>=0.9.1 which require users to update their torchvision to 0.9.1 only to fix this bug.

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• Did you write any new necessary tests? [not needed for typos/docs]
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[pep8speaks]

Hello @akihironitta! Thanks for updating this PR.

There are currently no PEP 8 issues detected in this Pull Request. Cheers! 🍻

Comment last updated at 2021-05-11 18:16:51 UTC

[codecov]

Codecov Report

Merging #633 (92277fb) into master (b236f21) will increase coverage by 0.03%.
The diff coverage is 90.00%.

@@            Coverage Diff             @@
##           master     #633      +/-   ##
==========================================
+ Coverage   71.83%   71.87%   +0.03%     
==========================================
  Files         118      118              
  Lines        7129     7146      +17     
==========================================
+ Hits         5121     5136      +15     
- Misses       2008     2010       +2     

Flag	Coverage Δ
cpu	71.87% <90.00%> (+0.03%)	⬆️
pytest	71.87% <90.00%> (+0.03%)	⬆️

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

Impacted Files	Coverage Δ
pl_bolts/utils/__init__.py	92.59% <86.66%> (-7.41%)	⬇️
pl_bolts/datasets/__init__.py	100.00% <100.00%> (ø)
pl_bolts/datasets/mnist_dataset.py	91.66% <100.00%> (+0.75%)	⬆️
pl_bolts/models/mnist_module.py	98.70% <100.00%> (ø)

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[Borda]

@akihironitta there seems to be some problem even with provided link, mind check the failing tests?

[Borda]

nice, thx :]