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

ngcpp
0.1.16

This version was deleted from PyPI around 2023-11-22. Installing fails with:
$ pip3 install ngcpp==0.1.16 ERROR: Could not find a version that satisfies the requirement ngcpp==0.1.16
View other deleted versions of ngcpp

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/2023-11-21/ \ ngcpp==0.1.16
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:
ngcpp-0.1.16-py3-none-any.whl (11.4KB)
ngcpp-0.1.16.tar.gz (9.5KB)