Code refactor

[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Refinement and optimization of the Ultralytics YOLOv5 codebase for better performance and maintenance.

📊 Key Changes

• Improved REST API route check for the POST method.
• Simplified file write permission check function removing an unnecessary conditional branch.
• Optimized checking for Chinese characters in strings using bool for clarity.
• Streamlined truthy check on file paths.
• Refined dataset downloading logic, prioritizing direct downloads over alternative methods.
• Cleaned up URL to file conversion function to be more concise.
• Updated image weighting function for simplicity and performance.
• Removed an unused list conversion in the coco80_to_coco91_class function.
• Enhanced logging output readability by using f-strings.
• Removed commented out code and unnecessary variables for clarity.

🎯 Purpose & Impact

• Ensure cleaner, more readable code, which makes it easier for developers to work on and contribute to the project. 🧹👨‍💻
• Performance tweaks might lead to minor speed improvements in file operations and data processing. ⚡️
• Logging improvements make it easier for users to follow what's happening, helping with debugging and general understanding. 🪵🔎
• Overall, these changes contribute to a more efficient and maintainable codebase, potentially reducing bugs and paving the way for future features. 🚀🔧