You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.
heroku-tl was reported malicious
OSV:MAL-2025-2967 - Malicious code in heroku-tl (PyPI)

heroku-tl
2.8.0

This version was deleted from PyPI around 2025-03-08. Installing fails with:
$ pip3 install heroku-tl==2.8.0 ERROR: Could not find a version that satisfies the requirement heroku-tl==2.8.0
View other deleted versions of heroku-tl

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/2025-03-07/ \ heroku-tl==2.8.0
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:
Heroku_TL-2.8.0-py3-none-any.whl (625.1KB)
Heroku-TL-2.8.0.tar.gz (555.0KB)