- Implement tests for retrieving a student's assignments, focus practices, finals, and returned worksheets in `test_my_tasks.py`.
- Ensure that the task list correctly reflects only the student's assignments and submissions.
- Add tests for quiz modes in `test_quiz_modes.py`, covering final quiz windows, sitting management, and grade release processes.
- Validate that only the class teacher can open final quiz windows and that practice is blocked while a final is active.
- Test the handling of photo submissions and the behavior of quiz sittings after deadlines.
