realpython.com

Practice how Python's .__dict__ attribute works for classes, instances, and functions, and when mappingproxy and __slots__ come into play.

Test your knowledge of Python profiling and performance tools. Practice identifying bottlenecks and using profilers like cProfile and timeit.

Explore how Python 3.14's lazy evaluation of annotations boosts performance, fixes chronic type hinting issues, and unlocks powerful new runtime uses.

Test your knowledge of annotations and type hints, including how different Python versions evaluate them at runtime.

Learn to profile Python programs with built-in and popular third-party tools, and turn performance insights into faster code.

Learn to write effective Python docstrings that clearly and professionally document your code using best practices and built-in conventions.

Test your Python knowledge in a skill quiz with basic to advanced questions. Are you a Novice, Intermediate, Proficient, or Expert?

Learn how to work with JSON data in Python using the json module. Convert, read, write, and validate JSON files and handle JSON data for APIs and storage.

Understand the difference between shallow and deep copies in Python. Learn how to duplicate objects safely using the copy module and other techniques.

Learn Python naming conventions with single and double underscores to design APIs, create safe classes, and prevent name clashes.