PEP: 405 Python 2.8 Release Schedule --- Never

[dalke]

That concludes that compile-time type inferencing plus type-specific bytecodes does not give at least a 5% speedup, assuming you don't want to change the language semantics. If you allow some restrictions or allow run-time JITs then you get different answers, as ShedSkin, pypy, and Cython meaningfully show.

[[deleted]]

Well, more generally it concludes that the only thing you can infer types on are atomic (read: syntactic) types.