Agent Skills: Mastering Python Skill

Mastering Python Skill

Production-ready Python patterns with runnable code examples.

Contents

• Workflow
• Reference Files
• Sample CLI Tools
• When NOT to Use
• Full Table of Contents

Workflow

Phase 1: Setup

1. Verify Python version

   python --version  # Require 3.10+, prefer 3.12+
   

2. Create and activate virtual environment

   python -m venv .venv && source .venv/bin/activate
   

3. Install dependencies

   poetry install  # or: pip install -r requirements.txt
   

Phase 2: Develop

4. Reference appropriate patterns:

   • Types → type-systems.md
   • Async → async-programming.md
   • APIs → fastapi-patterns.md
   • DB → database-access.md

5. Follow project structure from project-structure.md

Phase 3: Validate

6. Run quality checks

   ruff check . && ruff format --check .
   mypy src/
   

7. Run tests with coverage

   pytest -v --cov=src --cov-report=term-missing
   

Phase 4: Deploy

8. Build and verify package

   python -m build && twine check dist/*
   

9. Deploy per docker-deployment.md or ci-cd-pipelines.md

Pre-Completion Checklist:

- [ ] All tests pass
- [ ] mypy reports no errors
- [ ] ruff check clean
- [ ] Coverage ≥80%
- [ ] No security warnings in dependencies

Reference Files

| Category | Files | Key Topics | |----------|-------|------------| | Foundations | syntax-essentials, type-systems, project-structure, code-quality | Variables, type hints, generics, src layout, ruff, mypy | | Patterns | async-programming, error-handling, decorators, context-managers, generators | async/await, exceptions, Result type, with statements, yield | | Testing | pytest-essentials, mocking-strategies, property-testing | Fixtures, parametrize, unittest.mock, Hypothesis | | Web APIs | fastapi-patterns, pydantic-validation, database-access | Dependencies, middleware, validators, SQLAlchemy async | | Packaging | poetry-workflow, pyproject-config, docker-deployment | Lock files, PEP 621, multi-stage builds | | Production | ci-cd-pipelines, monitoring, security | GitHub Actions, OpenTelemetry, OWASP, JWT |

See TOC.md for detailed topic lookup.

Sample CLI Tools

Runnable examples demonstrating production patterns:

| Tool | Demonstrates | Reference | |------|-------------|-----------| | async_fetcher.py | Async HTTP, rate limiting, error handling | async-programming.md | | config_loader.py | Pydantic settings, .env files, validation | pydantic-validation.md | | db_cli.py | SQLAlchemy async CRUD, repository pattern | database-access.md | | code_validator.py | Run→check→fix with ruff and mypy | code-quality.md |

# Test examples
python sample-cli/async_fetcher.py https://httpbin.org/get
python sample-cli/config_loader.py --show-env
python sample-cli/db_cli.py init --sample-data && python sample-cli/db_cli.py list
python sample-cli/code_validator.py src/

When NOT to Use

• Non-Python languages: Use language-specific skills
• ML/AI model internals: Use PyTorch/TensorFlow skills
• Cloud infrastructure: Use AWS/GCP skills for infra (this covers code)
• Legacy Python 2: Focus is Python 3.10+