Python refactor and simplification

[glenn-jocher]

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🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Refactored and optimized code across major Python files for clarity and performance.

📊 Key Changes

• Simplified conditional and complex list comprehensions in various files.
• Streamlined subprocess arguments by removing unnecessary string conversions.
• Enhanced readability and compactness of the code by using ternary operators and better list/dict comprehensions.
• Improved performance of dictionary and list manipulations in training loops.
• Optimized logging and error messages for better user experience.
• Code style and formatting adjustments for better maintainability.

🎯 Purpose & Impact

• These changes improve the readability and maintainability of the codebase, making it easier for developers to understand and contribute.
• The reduced complexity and optimized logic could potentially offer minor performance benefits during execution.
• The overall user experience is enhanced with clearer logging and error reporting, aiding both users and developers in troubleshooting.