`importlib.util.spec_from_file_location` accepts `pathlib.Path`s

[thejohnfreeman]

I don't know in what version of Python this started, but importlib.util.spec_from_file_location accepts a pathlib.Path as the second argument, not just a str as mypy 0.701 seems to believe. Probably a quick fix for someone who knows the codebase better.

[srittau]

Added in 3.6 according to the docs. Patches welcome!

[thejohnfreeman]

@srittau If you can point me to the source file where spec_from_file_location is typed, and to the preferred PathLike or whatever type we need, I'll happily make the pull request.

[srittau]

@thejohnfreeman spec_from_file_location is typed in master/stdlib/3/importlib/util.pyi. An example of how to type something like this, including the necessary version check can be found here.