Upgrade PyO3 to 0.21 and switch to new API about polars HOT 6 CLOSED

Something about support for chrono? Need to get reminder from @stinodego

PyO3 has support for the Python datetime module:
https://pyo3.rs/main/doc/pyo3/types/struct.pydatetime

However, this was never available under the abi3 feature flag.

So we have a bunch of workarounds in place to materialize/read datetime objects. Specially, we have defined Python functions here:
https://github.com/pola-rs/polars/blob/main/py-polars/polars/_utils/convert.py

...that are called from Rust, for example here:

The 0.21 release notes mention:

Extended chrono / datetime conversions, including support for the abi3 feature and the chrono-tz crate

So I am expecting that we can now take advantage of native PyO3 datetime support. And I expect a good performance boost + code cleanup to come from this.

from polars.

0.21.1 is out, so I will start on this either this week or next.

from polars.

I'm gonna say this is done, insofar as it covers the main Polars repository, and the pyo3-polars issue is already filed for that repository.

from polars.

This is something I can help work on.

from polars.

Yes we will definitely upgrade to the new PyO3 version when it's released. I had planned to work on that myself but if it's something you're interested in working on I think it's fine if you want to do the honors here.

from polars.

Thanks a lot for the thorough work @itamarst !

from polars.