Odhiambo Washington writes:
This is the first time I am seeing this with MM3 so maybe it's something new in the latest releases?
IIRC you're one of the folks who creates a new venv and therefore gets upgrades of all prerequisite PyPI packages on upgrade. (Of course this is the recommended RightThing[tm].) If so, seems most likely that it's new in psycopg2.
psycopg2 has been released 3 times since Aug 5, most recently Oct 3, so it seems likely you've upgraded that package.
Try downgrading that package in the venv, to the version in the old venv if you have that available.
No log entry in any of the log files in /opt/mailman/mm/var/logs/.
Wouldn't expect them, since imports are early and the most likely relevant loggers (any that are in pyscopg2 itself) wouldn't be set up yet.