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

calcpy
1.2.1rc1

This version was deleted from PyPI around 2025-08-09. Installing fails with:
$ pip3 install calcpy==1.2.1rc1 ERROR: Could not find a version that satisfies the requirement calcpy==1.2.1rc1
View other deleted versions of calcpy

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/2025-08-08/ \ calcpy==1.2.1rc1
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:
calcpy-1.2.1rc1-py3-none-any.whl (43.8KB)
calcpy-1.2.1rc1.tar.gz (188.0KB)