TypedDict for structured dicts

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TypedDict lets you tell a type checker 'this dict will always have these specific keys with these types' - nothing more. At runtime, a TypedDict instance is just a plain dict. No runtime enforcement happens; you can still add or remove keys freely. The value comes entirely at static analysis time: mypy can warn you when you access a key that doesn't exist in the schema, or when you pass the wrong type for a value. This is ideal for data pipelines where you receive JSON-like dicts from an API and want type safety without the overhead of converting to dataclasses or Pydantic models. Notice that TypedDict is structural - any dict with the right keys and types satisfies the type, even if it was never declared as that TypedDict.