[3.8] int and fractions.Fraction report as having no `as_integer_ratio` member erroneously

[Starwort]

I would fix this if I understood the layout - but there is no builtins/fractions typing information in the /3/ folder that I can tell
Both (1).as_integer_ratio() and fractions.Fraction().as_integer_ratio() work in the console but throw errors with mypy

[srittau]

as_integer_ratio() was added in #3337 and your examples work for me with the latest mypy (0.761).

[JelleZijlstra]

As for your confusion about directory layout, the builtins module is in stdlib/2and3/ because we use the same file for Python 2 and 3.

[hauntsaninja]

Directory layout is documented in https://github.com/python/typeshed/blob/master/CONTRIBUTING.md#stub-versioning, let us know if that could be improved!