Topic 7. Iterators, generators, generator expressions, lambda functions, and decorators

Goal: learn to create and consume lazy sequences, combine itertools tools, choose sorting keys, and write typed decorators that preserve metadata.

Lecture contents

1. Iterators and generator functions — Iterables and iterators · Generator functions and yield
2. Lazy evaluation and itertools — Generator expressions and lazy evaluation · Ready-made itertools building blocks · A pipeline: temperature log
3. Lambda expressions and decorators — Lambda expressions and higher-order functions · A decorator as a function wrapper
4. Parameterized decorators — Parameterized decorators, retries, and timing · Debugging and common mistakes

Practice and review

• Practice — 3 worked examples with complete code
• Tasks — 30 variants, each with tasks at three difficulty levels
• Summary — conclusions, self-check questions, and useful links