Scope imports for torch.hub.list() improvement

[glenn-jocher]

🛠️ PR Summary

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🌟 Summary

Refactoring of model creation functions in hubconf.py.

📊 Key Changes

• Renamed create function to _create to indicate a private method not intended for external use.
• Delayed imports inside the _create function to potentially reduce import time and memory usage.
• Updated function calls from create to _create throughout the file.

🎯 Purpose & Impact

• The renaming hints to the developers that _create is an internal utility function, which helps maintain a clean and understandable codebase.
• Moving imports to function scope is a common best practice to streamline the initial load time of Python modules.
• This refactor slightly optimizes performance and may reduce memory footprint.
• The end-users of the library should not observe any direct changes in functionality due to these updates, ensuring backward compatibility. 🚀