Records: class vs dataclass vs namedtuple

Welcome to Objects & Data Modelling — the first pillar of the Advanced Python discipline. Python gives you several ways to model a bundle of data, and picking the right one is a daily design decision. This ladder starts there: a plain class, a dataclass, and a namedtuple, and when each earns its keep.

Each rung below is a three-panel workspace: instructions on the left, a code editor in the middle, and output + test results on the right.

• Run checks the visible tests you can read in the instructions.
• Submit grades your code against hidden tests (extra edge cases), so you can't pass by hard-coding the shown answers.
• The reference solution unlocks once you pass.

The code runs entirely in your browser (Pyodide — Python compiled to WebAssembly); nothing leaves your machine.

By the end you should be able to justify, out loud, why a given record is a frozen dataclass and not a namedtuple — the kind of small, sharp decision interviewers and reviewers probe.