# What this PR does
Remove
[`apps.get_model`](https://docs.djangoproject.com/en/3.2/ref/applications/#django.apps.apps.get_model)
invocations and use inline `import` statements in places where models
are imported within functions/methods to avoid circular imports.
I believe `import` statements are more appropriate for most use cases as
they allow for better static code analysis & formatting, and solve the
issue of circular imports without being unnecessarily dynamic as
`apps.get_model`. With `import` statements, it's possible to:
- Jump to model definitions in most IDEs
- Automatically sort inline imports with `isort`
- Find import errors faster/easier (most IDEs highlight broken imports)
- Have more consistency across regular & inline imports when importing
models
This PR also adds a flake8 rule to ban imports of `django.apps.apps`, so
it's harder to use `apps.get_model` by mistake (it's possible to ignore
this rule by using `# noqa: I251`). The rule is not enforced on
directories with migration files, because `apps.get_model` is often used
to get a historical state of a model, which is useful when writing
migrations ([see this SO answer for more
details](https://stackoverflow.com/a/37769213)). So `apps.get_model` is
considered OK in migrations (even necessary in some cases).
## Checklist
- [x] Unit, integration, and e2e (if applicable) tests updated
- [x] Documentation added (or `pr:no public docs` PR label added if not
required)
- [x] `CHANGELOG.md` updated (or `pr:no changelog` PR label added if not
required)
Make sure the final schedule is refreshed after dropping the cached ical
representations (sometimes the refresh final task was completed before
the cached ical files were refreshed).
