Ban lazy imports from airflow and airflow.models in codebase

[Taragolis]

Refers to:

• Ban import AirflowException from airflow #34512 (comment)
• Import Dataset from airflow.datasets to avoid circular dependency #34586 (comment)

This PR show what we should change before we could merge it.

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[uranusjr]

I think importing from airflow.models is mostly fine actually, since every one of those models eventually need to pull in most of the models anyway due to how SQLAlchemy’s ORM works. But if the check is simple why not, I guess.

[ephraimbuddy]

I think where we have issue is in importing from models when we are inside the models but every other imports in other places should work but of course, it’s better to ban it everywhere in the codebase, so this is good

[hussein-awala]

+1000

[Taragolis]

There are 500+ occurrence lazy imports in airflow codebase, without from airflow import __version__

In general every import should be excluded by up to 3 PRs:

1. Exclude from core + core tests + example dags
2. Exclude from providers + providers tests
3. Ban import in [tool.ruff.flake8-tidy-imports.banned-api]

What I have done with airflow.AirflowException locally:

1. Create in branch and in first commit was banned in[tool.ruff.flake8-tidy-imports.banned-api]
2. pre-commit run ruff --all-files
3. Resolve all cases in core, create second commit
4. pre-commit run ruff --all-files
5. Resolve all cases in providers, create third commit(s)
6. Check again that there is no any static checks failed
7. Create 3 branches from main and cherry pick changes
8. Create 3 PRs

[vincbeck]

Nice!

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