https://www.python.org/downloads/release/python-3510rc1/
Python Release Python 3.5.10rc1 | Python.org
The official home of the Python Programming Language
pythonrelease
https://mail.python.org/pipermail/mailman-users/2008-May/061542.html
[Mailman-Users] Running into a coding bug in 2.1.10 and 2.1.10rc1