code: def transform_courserun_schedule(self, content_metadata_item):
          
          start = content_metadata_item.get('start') or UNIX_MIN_DATE_STRING
          end = content_metadata_item.get('end') or UNIX_MAX_DATE_STRING
          return [{
              'startDate': parse_datetime_to_epoch_millis(start),
              'endDate': parse_datetime_to_epoch_millis(end),
              'active': current_time_is_in_interval(start, end)
          }]
docs: Return the schedule of the courseun content item.