Python 3.9
Python 3.9 was released in October 2020, received bug fixes until May 2022, and will receive security patches until October 2025.
PEG parser
One of the most significant changes in Python 3.9 is the rewrite of the parser that sits at the core of an interpreter. After 30 years of using the LL1 parser, which was quite useful for Python, the core development team decided to move to a more modern and powerful parser, which enabled many enhancements to the language – from new syntax to better error messages. While this did not result in any big change directly for developers, it has helped the language to continue evolving. Take a read at https://peps.python.org/pep-0617/ to understand the work that was done and how it is helping Python evolve.
Support for the IANA database
If you are working with time zones, you probably have used the IANA database (https://www.iana.org/time-zones) before. This database allows you to map strings to data that defines what offset...