Python · Mid-level · Theory

A service has a function def add_tag(tag, tags=[]), and after a few calls, the results start containing tags that belong to other calls. What's going on, and how do you fix it?

~4 min by voice

How to approach it

The interviewer wants to see whether you understand how Python evaluates default values and the difference between mutating an object and rebinding a name, not just whether you know the "None recipe".

Have you seen this question in a real interview?

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Topics

mutability data model

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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