You could write these common methods and publish them as a python package for everyone to load. Since pip can load directly from git, you need not really publish the package but ensure everyone pulls it from the git repo.
If you require not making it public, you could always host a simple git service on the same server like gitea exposed only on that server.
Another option would be to host the required programs as an Azure Function and expose them over HTTP. You can follow this quick start to get started with Azure Functions and Python.