mnist: src is no longer available

[FliegendeWurst]

Nixpkgs version

• Unstable (25.11)

Describe the bug

The directory the files were previously fetched from is empty: http://yann.lecun.com/exdb/mnist/
Is there a new source for these files?

Steps to reproduce

Try to build mnist without the FOD cache.

Expected behaviour

builds

Screenshots

No response

Relevant log output

Additional context

No response

System metadata

N/A

Notify maintainers

@CMCDragonkai

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[thunze]

Yann LeCun moved the dataset to Hugging Face but in a different format (announcement, HF dataset).

I was able to find two mirrors which claim to have permission from Yann LeCun to host the original files:

• Common Visual Data Foundation: https://github.com/cvdfoundation/mnist
  • URL pattern: https://storage.googleapis.com/cvdf-datasets/mnist/*
• PyTorch: datasets: Fallback to our own mirrors for mnist pytorch/vision#3544
  • URL pattern: https://ossci-datasets.s3.amazonaws.com/mnist/*