public IEnumerable <ScheduleItem> GetScheduleItemsByTimeSlotAndUser(EventAddress address, DateRangeAddress rangeAddress, Guid userID)
        {
            // if this is cached, you'll see schedule items on your list that used to be on the list but aren't anymore
            var result = repository.GetScheduleItemsByTimeSlotAndUser(address, rangeAddress, userID).FillTags(tagService);

            SetScheduleItemUsers(result);

            return(result);
        }