Python · Senior · Theory

What happens when you override eq in your class, and how does that relate to hash? How would you make an object that can safely be put in a set and used as a dictionary key?

~4 min by voice

How to approach it

This checks whether the candidate understands the contract between __eq__ and __hash__ and how lookup in a dict or set works. It also matters whether they can build hashable objects that don't break containers.

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data model dunder methods

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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

What happens when you override __eq__ in your class, and how does that relate to __hash__? How would you make an object that can safely be put in a set and used as a dictionary key?

How to approach it

Answer by voice

What happens when you override eq in your class, and how does that relate to hash? How would you make an object that can safely be put in a set and used as a dictionary key?