How would you explain Decorators to a junior engineer?

Answers use simple, clear English.

Quick interview answer

Explain Decorators in one sentence, then a tiny example, then one “don’t do this” tip. Common mistakes: Forgetting @wraps; decorator not returning wrapper function. Best practices: Use wraps; accept *args/**kwargs in generic decorators; prefer parameterized factory pattern.

Detailed answer

Junior-friendly explanation of Decorators: Plain English: Common mistakes: Forgetting @wraps; decorator not returning wrapper function. Best practices: Use wraps; accept *args/**kwargs in generic decorators; prefer parameterized factory pattern. Tiny example: Flask @app.route('/users') registers URL rule; @login_required guards view functions. One warning: Forgetting @wraps; decorator not returning wrapper function.

Full explanation

Keep jargon low, then layer detail. Decorators wrap functions: @decorator applies decorator(func). functools.wraps preserves __name__/__doc__. Common for logging, auth, caching, retries.

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Parent context — Decorators

Common mistakes: Forgetting @wraps; decorator not returning wrapper function. Best practices: Use wraps; accept *args/**kwargs in generic decorators; prefer parameterized factory pattern.

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