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

neqsim
2.5.22

This version was deleted from PyPI around 2025-09-02. Installing fails with:
$ pip3 install neqsim==2.5.22 ERROR: Could not find a version that satisfies the requirement neqsim==2.5.22
View other deleted versions of neqsim

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/2025-09-01/ \ neqsim==2.5.22
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Or, download files manually

And install manually via pip:
neqsim-2.5.22-py3-none-any.whl (54.3MB)
neqsim-2.5.22.tar.gz (54.3MB)