Fix bug #5044: Amazon dataset URLs are invalid!

[xei]

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Description

Checklist

• [x] Address all TODO's
• [x] Add alphabetized import to subdirectory's __init__.py
• [x] Run download_and_prepare successfully
• [x] Add checksums file
• [x] Properly cite in BibTeX format
• [x] Add passing test(s)
• [x] Add test data
• [x] If using additional dependencies (e.g. scipy), use lazy_imports (if applicable)
• [x] Add data generation script (if applicable)
• [x] Lint code