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

karellen-llvm-lldb
20.1.0rc1.post21

This version was deleted from PyPI around 2025-03-05. Installing fails with:
$ pip3 install karellen-llvm-lldb==20.1.0rc1.post21 ERROR: Could not find a version that satisfies the requirement karellen-llvm-lldb==20.1.0rc1.post21

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/2025-03-04/ \ karellen-llvm-lldb==20.1.0rc1.post21
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