Since we know what version of Python an installation of AWS CLI was last tested under (i.e. Python 3.9 if you installed the latest release today), we could add a soft warning message for when it finds itself running under a newer version. The message could encourage checking for an update from PyPI (possibly helping any future security fixes reach clients sooner).
This is just a nice to have, but it would be a good practice to incorporate, and it would be nice to have public example code to point other teams to who need a similar solution.
We should research what other teams have done in Python (I believe I have seen similar messages, but need to remember where), and replicate best practices we find elsewhere that address this functionality.