Decorators, generators, the GIL, and the rest of the language.
This is a spoken, conceptual discussion, not a live-coding exercise. You explain your reasoning out loud — concepts, tradeoffs, and "what would happen and why" — while the interviewer follows up and pushes on anything vague or surface-level.
Can you explain the difference between a list and a tuple in Python, and when you'd choose one over the other?
Can you explain what a decorator actually does under the hood in Python?
Can you explain the difference between a generator and a list, and why you'd choose one over the other for a large dataset?
Can you explain what the GIL is, and why it means threading doesn't give you true parallelism for CPU-bound work in Python?
Can you explain the difference between a classmethod, a staticmethod, and a regular instance method?
Can you explain the difference between catching a specific exception versus a bare except, and why the latter is usually discouraged?
Can you explain the difference between mutable and immutable types in Python, and a bug you've seen caused by mutable default arguments?
How do you manage dependencies and virtual environments in a Python project, and why does isolation matter?
These are a few examples — each real session pulls 5 questions at random from a larger pool across every category above, so repeat sessions won't repeat the same set.
5 free interviews every month, any track, no card required.