effective-python

Effective Python Skill

Apply the 90 items from Brett Slatkin's "Effective Python" (2nd Edition) to review existing code and write new Python code. This skill operates in two modes: Review Mode (analyze code for violations) and Write Mode (produce idiomatic Python from scratch).

Reference Files

This skill includes categorized reference files with all 90 items:

• ref-01-pythonic-thinking.md — Items 1-10: PEP 8, f-strings, bytes/str, walrus operator, unpacking, enumerate, zip, slicing
• ref-02-lists-and-dicts.md — Items 11-18: Slicing, sorting, dict ordering, defaultdict, missing
• ref-03-functions.md — Items 19-26: Exceptions vs None, closures, *args/**kwargs, keyword-only args, decorators
• ref-04-comprehensions-generators.md — Items 27-36: Comprehensions, generators, yield from, itertools
• ref-05-classes-interfaces.md — Items 37-43: Composition, @classmethod, super(), mix-ins, public attrs
• ref-06-metaclasses-attributes.md — Items 44-51: @property, descriptors, getattr, init_subclass, class decorators
• ref-07-concurrency.md — Items 52-64: subprocess, threads, Lock, Queue, coroutines, asyncio
• ref-08-robustness-performance.md — Items 65-76: try/except, contextlib, datetime, decimal, profiling, data structures
• ref-09-testing-debugging.md — Items 77-85: TestCase, mocks, dependency injection, pdb, tracemalloc
• ref-10-collaboration.md — Items 86-90: Docstrings, packages, root exceptions, virtual environments

How to Use This Skill

Before responding, read the relevant reference files based on the code's topic. For a general review, read all files. For targeted work (e.g., writing async code), read the specific reference (e.g., ref-07-concurrency.md).

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Mode 1: Code Review

When the user asks you to review existing Python code, follow this process:

Step 1: Read Relevant References

Determine which chapters apply to the code under review and read those reference files. If unsure, read all of them.