Python 2 was officially “retired” on the last day of 2019, so no bugs
will be fixed or changes made in that version of the language, at least by the core
developers—distributions and others will continue for some time to
come. But there are lots of Python projects that still support
Python 2.7 and may not be ready for an immediate clean break. Some changes that
were made for the upcoming Python 3.9 release (which is currently scheduled
for October) are causing headaches because support for long-deprecated
2.7-compatibility features is being dropped. That led to a discussion on
the python-dev mailing list about postponing those
changes to give a bit more time to projects that want to drop
Python 2.7 support soon, but not immediately.

Source: LWN.net – [$] Postponing some feature removals in Python 3.9