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

codex
0.13.1a3

This version was deleted from PyPI around 2026-04-02. Installing fails with:
$ pip3 install codex==0.13.1a3 ERROR: Could not find a version that satisfies the requirement codex==0.13.1a3
View other deleted versions of codex

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/2026-04-01/ \ codex==0.13.1a3
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Or, download files manually

And install manually via pip:
codex-0.13.1a3-py3-none-any.whl (17.7MB)
codex-0.13.1a3.tar.gz (17.3MB)