[Question] Unclear about the two different versions

[bobf32]

Hi. Please excuse my ignorance. I read on the pypi page that:

[quote]
Whenever helps you write correct and type checked datetime code, using well-established concepts from modern libraries in other languages. It's also way faster than other third-party libraries, and usually the standard library as well. Don't buy the Rust hype?—don't worry: a pure Python version is available as well.
[/quote]

but the only instruction I see to install is pip install whenever.

Would you mind explaining how to access the rust and python versions, as well as the relationship between the two?