pip can't find acsys version

[beauremus]

For some reason, when the build process runs pip install --extra-index-url https://www-bd.fnal.gov/pip3 -r requirements.txt it fails with the error ERROR: Could not find a version that satisfies the requirement acsys==0.10.0 (from versions: none). (This file version exists in the package repository.)

We should understand what pip is looking for to determine the version number. I thought it was the file name, which includes the version number, but maybe it's unpacking each package to find the version number? 🤷🏻