Despite the majority of compatibility layers vanishing in Python 3.9, it's been decided to make a few exceptions for some 2.7 compatibility laters to support Python projects maintainers, so that ...

PSF is urging its legion of Python users to upgrade systems to Python 3.8.8 or 3.9.2, in particular to address the remote code execution (RCE) vulnerability that's tracked as CVE-2021-3177.