Mastering Python Second Edition Exercises

This repository contains solutions for the exercises in Mastering Python, Second Edition. Each solution_00.py is the maintained, typed reference solution. Higher-numbered solution_NN.py files and specialized solution files are community alternatives.

Requirements

Development requires Python 3.10 or newer, uv, and Lefthook. On macOS, install the tools, synchronize every dependency group, and install the Git hooks:

$ brew install uv lefthook
$ uv sync --all-groups
$ lefthook install

Running exercises

Each exercise_NN directory contains its exact question, a concise explanation, the canonical answer in solution_00.py, its dependencies, and focused tests. Run an answer or its tests from the repository root. For example:

$ uv run python CH_04_design_patterns/exercise_01/solution_00.py
$ uv run pytest CH_04_design_patterns/exercise_01/test_solution_00.py

Run all checks

Run the complete formatting, linting, type-checking, and test suite before submitting changes:

$ uv run ruff format --check .
$ uv run ruff check .
$ uv run pyrefly check
$ uv run mypy .
$ uv run pyright
$ uv run pytest

Dependency groups

The lockfile contains separate dependency groups so an exercise can use only the tools it needs:

dev

Documentation rendering, formatting, linting, type-checking, and tests.

interactive

Interactive Python, widgets, terminal colors, and completion support.

scientific

Numerical, tabular, notebook, and visualization tools.

nlp

Natural-language processing and its command-line support.

native

Native-extension build tools and C foreign-function interfaces.

packaging

Distribution builds, wheels, and isolated environment testing.

Install a single optional group when working only in that domain:

$ uv sync --group interactive

After the package cache has been populated, reproduce the complete locked environment without network access:

$ uv sync --all-groups --locked --offline

Contributing

Alternative solutions are welcome and use the next available solution_NN.py. Keep canonical files, tests, and exercise documentation unchanged unless correcting the reference answer. All submitted Python code must be formatted, linted, typed, and tested. Higher-numbered and specialized community alternatives are intentionally excluded from automated canonical gates to preserve historical files. New alternative pull requests must include focused tests and report equivalent per-file Ruff, Pyrefly, mypy, and Pyright results. The repository-wide commands above validate the maintained canonical scope.