You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.
lightgboost was reported malicious
OSV:MAL-2025-191781 - Malicious code in lightgboost (PyPI)

lightgboost
1.1.1

This version was deleted from PyPI around 2025-02-06. Installing fails with:
$ pip3 install lightgboost==1.1.1 ERROR: Could not find a version that satisfies the requirement lightgboost==1.1.1
View other deleted versions of lightgboost

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/2025-02-05/ \ lightgboost==1.1.1
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Or, download files manually

And install manually via pip:
lightgboost-1.1.1-py3-none-any.whl (1.6KB)
lightgboost-1.1.1.tar.gz (1.5KB)