Ruff RUF refactor

[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Refactors and cleans up YOLOv3 codebase for readability, logging consistency, and modern Python typing, with minimal behavior changes but a likely bump to Python 3.10+ due to new type hint syntax. ✨

📊 Key Changes

• Code hygiene: renamed unused variables (prefixed with “_”) across modules to silence linters and clarify intent.
• Logging/printing polish:
  • Consistent f-string formatting using !s for safe string conversion.
  • Clearer layer/model parse logs in TensorFlow and PyTorch models.
  • Improved CSV logging headers/rows using iterable unpacking.
• Type hints and imports:
  • Adopted modern union types (e.g., dict | None, torch.Tensor | tuple[...]) and added from __future__ import annotations.
  • Removed unnecessary noqa comments; minor import cleanup (e.g., OpenVINO).
• Minor API/utility tweaks:
  • hubconf.py: use next(iter(rglob(...))) to fetch model YAML.
  • letterbox: simplified rounding without changing behavior.
  • Safer and clearer list/tuple construction with iterable unpacking (e.g., [*types, triton], [*names, "background"]).
  • Plotting/utilities: avoid unused variables (underscore naming), small formatting updates.

🎯 Purpose & Impact

• Cleaner, more maintainable code ✅
  • Easier to read and debug with improved logs and consistent formatting.
• Fewer linter warnings and reduced noise 🧹
  • Unused variables and redundant comments removed.
• Modern typing improves developer ergonomics 🧠
  • Clearer function contracts; better IDE support.
• Potential Python version impact ⚠️
  • Use of union types (|) likely requires Python 3.10+.
• Minimal runtime behavior change for users 🧪
  • Inference, training, and exports should behave the same, with slightly clearer logs and CSV outputs.

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[UltralyticsAssistant]

🎉 Merged! Huge thanks, @glenn-jocher, for the thoughtful refactor in PR #2357. As Antoine de Saint-Exupéry said, “Perfection is achieved not when there is nothing more to add, but when there is nothing left to take away”—this cleanup embodies that spirit.

Your improvements—consistent logging, modern Python typing, clearer parsing logs, and leaner utilities—make YOLOv3 easier to read, debug, and maintain, with minimal behavior changes for users. The move toward Python 3.10+ typing will pay dividends for developer ergonomics and long-term sustainability. This is the kind of polish that keeps our tools sharp and our community productive.

Appreciate the care and craft you put into this. Onward! 🚀

[UltralyticsAssistant]

🔍 PR Review

_{Made with ❤️ by Ultralytics Actions}

Thanks for the tidy-up—everything looks good to me and I didn’t spot any issues. ✅