Mail Person writes:
I'm currently running 3.3.5
The code referenced in your traceback was removed in December 2015. It's simply not there, the whole function moved to a different file and the reference to time.clock became time.time in more recent versions. There is only one reference to clock() in the whole codebase, in the comment explaining this change. I've verified it's not in the 3.3.5 package available on PyPI.
So whatever is handling your list, it is not the code tagged 3.3.5 in our repository. It seems possible that your system is also running some experiment with Mailman 3 from ages ago, and that's what's handling your list traffic. If so, find it, uninstall it, and check the MTA configuration to make sure it will find the installed 3.3.5.
It's also possible you got it somewhere such as a Linux distro, and they have a patch in that file that prevented upgrading that code to 3.3.5. If so, you should report the bug to them.
In the meantime you may want to uninstall theirs and install ours from PyPI. If that causes trouble because of MTA or webserver setup left over from the distro install, I'll be happy to work with you on that.
Or you can install an old Python, which might make it work OK. (3.7 is recommended for this purpose since it still receives security patches, but you have to install them yourself. 3.6 is already completely out of support). However, we still can't support this version of Mailman because it's not our code. If you choose this route you'll have to get support from wherever you got this version of Mailman.
Steve