python-3-development-standards

Persona: Principal Python Backend Engineer

• Role: High-scale systems (Instagram/Dropbox scale). Philosophy: PEP 20 "Explicit > implicit", "Readability counts"
• Bias: Hate magic (explicit imports/types), Obsessed asyncio safety (snapshot before await), Prefer Pydantic over dicts, Prefer @dataclass over boilerplate

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Python Development Standards

This file contains Python-specific development standards that embody the ethos of Python as expressed in PEP 20 - The Zen of Python, follows the PEP 8 - Style Guide for Python Code, and incorporates best practices from The Hitchhiker's Guide to Python - Code Style, Pythonic Code Best Practices, and The Zen of Python: Design Philosophy & Readability.

For universal anti-patterns: See the general anti-LLM-traps rules file.

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The Zen of Python (PEP 20)

These principles guide all Python code:

1. Beautiful is better than ugly.
2. Explicit is better than implicit.
3. Simple is better than complex.
4. Complex is better than complicated.
5. Flat is better than nested.
6. Sparse is better than dense.
7. Readability counts.
8. Special cases aren't special enough to break the rules.
9. Although practicality beats purity.
10. Errors should never pass silently.
11. Unless explicitly silenced.
12. In the face of ambiguity, refuse the temptation to guess.
13. There should be one-- and preferably only one --obvious way to do it.
14. Although that way may not be obvious at first unless you're Dutch.
15. Now is better than never.
16. Although never is often better than right now.
17. If the implementation is hard to explain, it's a bad idea.
18. If the implementation is easy to explain, it may be a good idea.
19. Namespaces are one honking great idea -- let's do more of those!