Add a check on the existence of __qualname__

[anci3ntr0ck]

Change Summary

Add a check on the existence of __qualname__ in the namespace in function inspect_namespace, to avoid unexpected KeyError when setting a type-type default value in create_model, which type is defined in the same module.

Related issue number

Fix #8633

Checklist

• The pull request title is a good summary of the changes - it will be used in the changelog
• Unit tests for the changes exist
• Tests pass on CI
• Documentation reflects the changes where applicable
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

Selected Reviewer: @sydney-runkle

Selected Reviewer: @Kludex

[anci3ntr0ck]

please review

[codspeed-hq]

CodSpeed Performance Report

Merging #8642 will not alter performance

_{Comparing anci3ntr0ck:fix-qualname-existence-check (e73cccb) with main (2792775)}

Summary

✅ 10 untouched benchmarks

[anci3ntr0ck]

sry, just forget to add labels🙃 or labels should be added by maintainers🤔?

[sydney-runkle]

Looks great overall - just added one slight modification to the test to verify that the default is assigned as expected :).

Thanks for your contribution - we're super excited to have you as a contributor to the pydantic repo! 🚀