You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.

alpaqa
1.0.0a3

This version was deleted from PyPI around 2023-11-16. Installing fails with:
$ pip3 install alpaqa==1.0.0a3 ERROR: Could not find a version that satisfies the requirement alpaqa==1.0.0a3

Install through StableBuild

You can install this package from StableBuild's PyPI snapshots from before the version was deleted:
pip3 install \ -i https://YOUR_API_KEY.pypimirror.stablebuild.com/2023-11-15/ \ alpaqa==1.0.0a3
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