Summary:
Unfortunately the more time I've spent with this the more I've realized how poorly the whole `polars` import in `fbsource` (`third-party/pypi:polars` + `third-party/rust:polars` + `third-party/rust:polars-py`) has been done. To be fair it is quite a complicated use case and definitely the largest dep footprint Rust/Python module in all of `fbsource`. For more context see T179532760 but this is the 1st step of many to fix everything and hopefully move `polars` out of `third-party/rust` completely.
That said, the work here allows me to land `1.76.0` without having to upgrade `pyo3` + `polars` + `libcst` + tons of other crates (stack @ D53776888) and do that with more time on my hands post land.
Reviewed By: dtolnay
Differential Revision: D53858402
fbshipit-source-id: 3644897f2b569ebc23463dd35aba77bd5c59fca6
ce99a9536c