Feature/private methods

[FBumann]

Description

Make some internaly usd methods private to reduce the namespace. Mostly cosmetic

Motivation and Context

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• My code follows the project's code style (run ruff check and ruff format)
• I have added tests that prove my fix/feature works
• All new and existing tests pass (pytest test/)
• I have updated the documentation if needed

[julian-belina]

Should this also be integrated into version 3.1.0, @FBumann?

[FBumann]

Should this also be integrated into version 3.1.0, @FBumann?

I dont care to be honest.
For me its fine to do this in the upcoming weeks. Its just a patch. We can also leave them public.