Unfortunately stuff like this never makes it to the upstream. And i am afraid to ask why. We had pypy for years, but never got merged with python. That is why there are still minor incompatibilities between pypy and "The Python", so it's not that useful as it might have been if it got merged with cpython at some point.
It's not like you can just "merge" pypy into python, they are totally different implementations. CPython is written in C and PyPy is written in RPython which is a subset of the python language that gets compiled, into into an interpreter with JIT support. You can actually write an interpreter for any language using RPython and their toolset, for example Ruby https://github.com/topazproject/topaz