'Course is created here and shared by all the class\'s tests.'

@classmethod
def setUpClass(cls):

    super(TestFieldOverrides, cls).setUpClass()
    cls.course = CourseFactory.create()
    cls.course.enable_ccx = True
    start = datetime.datetime(2010, 5, 12, 2, 42, tzinfo=pytz.UTC)
    due = datetime.datetime(2010, 7, 7, 0, 0, tzinfo=pytz.UTC)
    chapters = [ItemFactory.create(start=start, parent=cls.course) for _ in xrange(2)]
    sequentials = flatten([[ItemFactory.create(parent=chapter) for _ in xrange(2)] for chapter in chapters])
    verticals = flatten([[ItemFactory.create(due=due, parent=sequential) for _ in xrange(2)] for sequential in sequentials])
    blocks = flatten([[ItemFactory.create(parent=vertical) for _ in xrange(2)] for vertical in verticals])
