Fix ROOT as relative path

[maltelorbach]

Make it possible again to run yolo code from outside the yolo root directory.

Closes #5065

🛠️ PR Summary

_{Made with ❤️ by Ultralytics Actions}

🌟 Summary

Improvement in path handling across YOLOv5 scripts.

📊 Key Changes

• Added the os module import for enhanced path operations.
• Modified the way the ROOT directory is determined to be relative to the current working directory by using os.path.relpath instead of the previously used Path.relative_to.

🎯 Purpose & Impact

• Consistency: This change ensures a consistent and robust way of identifying relative paths across different environments and operating systems. 🧭
• Portability: By using os.path.relpath, there is an increased likelihood of cross-platform compatibility, preventing potential path-related issues when running on different systems. 💻🌍
• Code Reliability: These changes aim to minimize the risks of path errors that users might face when setting up YOLOv5, leading to a smoother user experience. 👌

This update is mainly behind-the-scenes and should be seamless to users, but it will contribute to making the software more stable and dependable.

[github-actions]

👋 Hello @maltelorbach, thank you for submitting a 🚀 PR! To allow your work to be integrated as seamlessly as possible, we advise you to:

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[glenn-jocher]

@maltelorbach thanks for the PR! I'm curious if there's any benefit to import os.path instead of import os?

[glenn-jocher]

@maltelorbach PR is merged. Thank you for your contributions to YOLOv5 🚀 and Vision AI ⭐

[maltelorbach]

@maltelorbach thanks for the PR! I'm curious if there's any benefit to import os.path instead of import os?

Ah, no, not really. It's my tendency to make imports as explicit as possible. But simply import os is just as good imo.