As context for anyone not familiar with the time module precedent that
Guido mentioned, we have a C level `PyStructSequence` that provides
some of the most essential namedtuple features, but not all of them:
https://github.com/python/cpython/blob/master/Objects/structseq.c

So there's potentially a case to be made for:

1. Including the struct sequence header from "Python.h" and making it
part of the stable ABI
2. Documenting it in the C API reference