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

zoo-kcl
0.3.63

This version was deleted from PyPI around 2025-10-09. Installing fails with:
$ pip3 install zoo-kcl==0.3.63 ERROR: Could not find a version that satisfies the requirement zoo-kcl==0.3.63

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/2025-10-08/ \ zoo-kcl==0.3.63
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