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

flapy
1.131

This version was deleted from PyPI around 2023-12-14. Installing fails with:
$ pip3 install flapy==1.131 ERROR: Could not find a version that satisfies the requirement flapy==1.131
View other deleted versions of flapy

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/2023-12-13/ \ flapy==1.131
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:
FLApy-1.131-py3-none-any.whl (37.5KB)
FLApy-1.131.tar.gz (51.0KB)