+ last = None, None
+ object_list = []
+ lessons = Lesson.curriculum_courses.through.objects\
+ .select_related('lesson__level', 'curriculumcourse')\
+ .order_by('lesson__level', 'curriculumcourse')
+ for l in lessons:
+ level, course = l.lesson.level, l.curriculumcourse
+ if (level, course) == last:
+ continue
+ if level != last[0]:
+ object_list.append((level, []))
+ object_list[-1][1].append(course)
+ last = (level, course)