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[glenn-jocher]

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improved dataset verification process in YOLOv5.

📊 Key Changes

• Tweaked the condition that handles missing class names to provide default values.
• Adjusted dataset path resolution logic to ensure validation path existence.

🎯 Purpose & Impact

• Ensures datasets without specified class names receive appropriate default names, preventing potential errors.
• Strengthens the verification of dataset validation paths, improving the reliability of model training and evaluation, which is beneficial for developers and users working on machine learning projects. 📈