Lists, Tuples, and Sets
Store ordered and unordered collections of data with lists, tuples, and sets — and know when to use each.
Dictionaries and Nested Records
Store key-value data with dictionaries, work with nested structures, and use defaultdict and Counter.
Iteration, Comprehensions, and Generators
Loop over data efficiently using for loops, enumerate, zip, comprehensions, and memory-efficient generators.
Copying and Mutability
Understand mutable vs immutable types, shallow vs deep copies, and how to avoid accidental data mutation bugs.
Choosing the Right Container
A practical guide to picking lists, tuples, sets, dicts, or collections module types for any situation.