Advanced Django query

This code prints the following results:

id name due_date status controls_list frequency created last_updated due_date 1 ScheduledTask,LeapMotion 1/1/2015 Ok Overdue 1/1/2015 1/1/2015 2 ScheduledTask,LeapMotion 1/2/2015 Ok Overdue 1/2/2015 1/2/2015 3 ScheduledTask,LeapMotion 1/3/2015 Ok Overdue 1/3/2015 1/3/2015

tasks = list(
  ScheduledTask.objects.filter(system=system, completed=False)
  .filter(Q(controls__compliance_level=system.compliance_level) | Q(controls__isnull=True))
  .annotate(
    status=Case(
      When(due_date__lt=dt.now(), then=Value("Overdue")),
      default=Value("Ok"),
      output_field=CharField(max_length=10),
    )
  )
  .annotate(controls_list=StringAgg("controls__control_id", ", "))
  .values(
    "id", "name", "due_date", "status", "controls_list", "frequency", "created", "last_updated", "due_date"
  )
)