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

viktor
13.7.0rc3

This version was deleted from PyPI around 2024-08-08. Installing fails with:
$ pip3 install viktor==13.7.0rc3 ERROR: Could not find a version that satisfies the requirement viktor==13.7.0rc3

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/2024-08-07/ \ viktor==13.7.0rc3
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