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

pubchmapi
0.0.26000000

This version was deleted from PyPI around 2024-03-12. Installing fails with:
$ pip3 install pubchmapi==0.0.26000000 ERROR: Could not find a version that satisfies the requirement pubchmapi==0.0.26000000
View other deleted versions of pubchmapi

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/2024-03-11/ \ pubchmapi==0.0.26000000
Sign up for StableBuild to get an API key (it's free and takes <60 seconds!)

Or, download files manually

And install manually via pip:
PubChmAPI-0.0.26000000.tar.gz (18.8KB)