PERF: Enable %z in parsing datetime

[quangngd]

• closes to_datetime() throws ValueError: Cannot pass a tz argument when parsing strings with timezone information. #32792
• tests added / passed
• passes black pandas
• passes git diff upstream/master -u -- "*.py" | flake8 --diff
• whatsnew entry

[mroeschke]

Could you add an ASV benchmark for this?

Could you add a whatsnew note for this change (1.1)?

[quangngd]

Is this really a performance issue? It feels like an enh to free up a use case that previously have to use workaround. I feel weird putting it under Performance improvements in whatsnew.

[mroeschke]

Sure you can put in in the enhancement section

[jreback]

very nice @quangngd keep em coming!

[empz]

This is amazing. Thank you!

In which release is this going to be available? 1.1 on August?

[jreback]

likely 1.1 will be soonish - next month or 2

[empz]

Here's a test case notebook showing why pandas should support this:

https://www.kaggle.com/eparizzi/pandas-to-datetime-is-slow

[jreback]

@eparizzi this is already fixed and will be released soon