Python · Junior · Theory

Imagine a function add with a parameter items whose default value is an empty list. The function appends an element to that list and returns it. What happens if you call it twice in a row without passing the second argument?

~4 min by voice

How to approach it

They're checking whether the candidate understands when Python evaluates default parameter values and why a mutable object as a default becomes shared across all calls. Plus whether they can fix it idiomatically.

Have you seen this question in a real interview?

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data model functions

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Answer by voice

The interviewer will ask this question and listen. Think out loud and ask for a hint if you need one. When you're done, pause or tap “That's my answer”. In about a minute, your score and the points you covered show up here.

Best with headphones · ~4 min