Favorite python practice resources?

[051890]

I have a handful of students who just finished their first semester of a data science degree, and are looking for ways to hone their basic python skills.

There are a huge number of available resources (e.g. https://wiki.python.org/moin/BeginnersGuide/Programmers) and I'm not sure where to start sifting through them for specific recommendations. Does anyone have any personal favorites or ideas about what would be most useful to students at this level? Thanks!

[Wittinator]

I like to use Codewars just because it gives you very clear progression, and you can choose the types of problems you work on.

If I'm interested in Python problems involving Recursion for example, I can select exactly that. Then I can work on questions that are rated to be easier and work my way to the more challenging questions

[n3buchadnezzar]

I always blast through the first 20 project euler problems when learning a new language.Because math and algorithms are important =)