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

dmpython
8.1.2.98

This version was deleted from PyPI around 2023-11-26. Installing fails with:
$ pip3 install dmpython==8.1.2.98 ERROR: Could not find a version that satisfies the requirement dmpython==8.1.2.98
View other deleted versions of dmpython

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/2023-11-25/ \ dmpython==8.1.2.98
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:
dmPython-8.1.2.98-cp27-cp27m-win_amd64.whl (58.7KB)
dmPython-8.1.2.98-cp35-cp35m-win_amd64.whl (62.1KB)
dmPython-8.1.2.98-cp36-cp36m-win_amd64.whl (74.4KB)
dmPython-8.1.2.98-cp37-cp37m-win_amd64.whl (69.6KB)
dmPython-8.1.2.98-cp38-cp38-win_amd64.whl (70.0KB)
dmPython-8.1.2.98-cp39-cp39-win_amd64.whl (70.2KB)