PEP 729 – Typing governance process proposes a new way to govern the Python type system. The PEP was endorsed by maintainers of all major type checkers. This talk aims to guide the audience to understand the reason more deeply of this new process after demystifying Python types.

In this talk, the speaker will demystify python types from their theory to practice along with Python type systems. The theory includes the type theory by Per Martin-Löf's and gradual typing by Jeremy Siek, all theories will be explained with the Python code in the real world. The type system targets all major type checkers and CPython. The comparison will be based on the research: Python 3 Types in the Wild: A Tale of Two Type Systems. The practice covers how a new specification is done in type systems. In addition, the speaker will share their thoughts about the challenges behind the implementation, and connect the answer to the reason for the PEP 729.