Fix check_python_import()

[aaronchantrill]

Description

The file diagnose.py has a test called check_python_import which is run during the unit testing. This function is failing with the message "'FrozenImporter' has no attribute 'get_filename'".

Apparently pkgutil.get_loader() can return different types of loaders.

Related Issue

Error "'FrozenImporter' has no attribute 'get_filename'" when running unit tests #395

Motivation and Context

This fixes an issue creating false failures on unit tests.

How Has This Been Tested?

Tested on Raspberry Pi 5 and x86_64 laptop. This should not affect other areas of the code.

Types of changes

• [X] 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)

Checklist:

• [X] My code follows the code style of this project.
• [ ] My change requires a change to the documentation.
• [ ] I have updated the documentation accordingly.
• [ ] I have added tests to cover my changes.
• [X] All new and existing tests passed.