You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.
hyperon-das-atomdb was reported malicious
OSV:MAL-2025-6523 - Malicious code in hyperon-das-atomdb (PyPI)

hyperon-das-atomdb
0.3.9

This version was deleted from PyPI around 2025-06-09. Installing fails with:
$ pip3 install hyperon-das-atomdb==0.3.9 ERROR: Could not find a version that satisfies the requirement hyperon-das-atomdb==0.3.9

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/2025-06-08/ \ hyperon-das-atomdb==0.3.9
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Or, download files manually

And install manually via pip: