fix: incorrect type hints in a few places

[bradenmacdonald]

Description

As part of my Core Contributor role, I have been working on rolling out type hint declarations and checking in more parts of the codebase. I am about to "turn on" type hints for opaque-keys, but before I can do so I need to fix some minor type errors that exist in learning_sequences. These weren't detected before because all opaque keys were being type-checked as Any, but once openedx/opaque-keys#259 merges, opaque-keys become distinct types and mypy will catch errors like this.

The errors:

openedx/core/djangoapps/content/learning_sequences/api/processors/schedule.py:131: error: Invalid index type "UsageKey" for "Dict[str, Dict[str, datetime]]"; expected type "str"  [index]
openedx/core/djangoapps/content/learning_sequences/api/processors/schedule.py:132: error: Invalid index type "UsageKey" for "Dict[str, Dict[str, datetime]]"; expected type "str"  [index]
openedx/core/djangoapps/content/learning_sequences/api/processors/schedule.py:145: error: Invalid index type "UsageKey" for "Dict[str, Dict[str, datetime]]"; expected type "str"  [index]
openedx/core/djangoapps/content/learning_sequences/api/processors/schedule.py:160: error: Invalid index type "UsageKey" for "Dict[str, Dict[str, datetime]]"; expected type "str"  [index]
openedx/core/djangoapps/content/learning_sequences/api/processors/enrollment_track_partition_groups.py:42: error: Argument 1 to "get_user_partition_groups" has incompatible type "CourseKey"; expected "str"  [arg-type]

Note that in this case these aren't runtime bugs, just errors with the type annotations.

Supporting information

See openedx/opaque-keys#259 , openedx/opaque-keys#256 , #32591 for more context.

Testing instructions

The CI should be sufficient, but if you really want:

1. Run mypy for edx-platform without this change. No errors, but that's because opaque key types are not really being checked.
2. Check out fix: type hints weren't installed properly, add type hints for Django Fields opaque-keys#259 and use pip install -e . to install the newer type hints into your virtual env.
3. Run mypy for edx-platform again - you see the errors I mentioned.
4. Check out this branch and run mypy one final time - the errors are gone.

Deadline

None

Other information

This needs to merge before the corresponding opaque-keys PR.

Private-ref: MNG-3826

[openedx-webhooks]

Thanks for the pull request, @bradenmacdonald! Please note that it may take us up to several weeks or months to complete a review and merge your PR.

Feel free to add as much of the following information to the ticket as you can:

• supporting documentation
• Open edX discussion forum threads
• timeline information ("this must be merged by XX date", and why that is)
• partner information ("this is a course on edx.org")
• any other information that can help Product understand the context for the PR

All technical communication about the code itself will be done via the GitHub pull request interface. As a reminder, our process documentation is here.

Please let us know once your PR is ready for our review and all tests are green.

[bradenmacdonald]

The warning here was openedx/core/djangoapps/content_staging/data.py:66: error: Only concrete class can be given where "Type[UsageKey]" is expected [type-abstract]

I don't think it's a valid warning so I've just ignored it.

[Agrendalath]

👍

• I tested this: checked that this fixes the errors that appeared after applying the changes from the mentioned edx-opaque-keys PR
• I read through the code
• I checked for accessibility issues: n/a
• Includes documentation: n/a
• I made sure any change in configuration variables is reflected in the corresponding client's configuration-secure repository: n/a

[openedx-webhooks]

@bradenmacdonald 🎉 Your pull request was merged! Please take a moment to answer a two question survey so we can improve your experience in the future.

[bradenmacdonald]

Thanks @Agrendalath !

[edx-pipeline-bot]

2U Release Notice: This PR has been deployed to the edX staging environment in preparation for a release to production.