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

fastjet
3.4.0.0rc1

This version was deleted from PyPI around 2024-05-15. Installing fails with:
$ pip3 install fastjet==3.4.0.0rc1 ERROR: Could not find a version that satisfies the requirement fastjet==3.4.0.0rc1

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/2024-05-14/ \ fastjet==3.4.0.0rc1
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