Sorting doesn't return a new list

What this problem practises

The two sorting APIs are not interchangeable: sorted() returns a brand-new list while list.sort() sorts in place and returns None. Key functions compare the values they extract, and comparing mixed types raises TypeError.

This is an output-prediction problem: read the snippet carefully and write down exactly what it prints before anything runs. These questions are interview staples because they test whether you know the language rules, or merely recognise their syntax.

Difficulty: medium — expect to hold two interacting rules in your head at once, such as a boundary combined with a mutation.

The challenge

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Keep going

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