You're looking at StableBuild's Deleted PyPI mirror - where we index all deleted packages from the Python package registry.
dev-server-python was reported malicious
OSV:MAL-2025-191717 - Malicious code in dev-server-python (PyPI)

dev-server-python
99.9.9

This version was deleted from PyPI around 2025-12-03. Installing fails with:
$ pip3 install dev-server-python==99.9.9 ERROR: Could not find a version that satisfies the requirement dev-server-python==99.9.9
View other deleted versions of dev-server-python

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/2025-12-02/ \ dev-server-python==99.9.9
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:
dev_server_python-99.9.9-py3-none-any.whl (1.1KB)
dev_server_python-99.9.9.tar.gz (1.1KB)