public static TimeSpan GetTravelTime(this Journey journey)
        {
            DateTime utcDeptDateTime = journey.GetUTCDeptDateTime();
            DateTime utcArrvDateTime = journey.GetUTCArrvDateTime();

            if (utcDeptDateTime != default(DateTime) && utcArrvDateTime != default(DateTime))
            {
                return(utcArrvDateTime.Subtract(utcDeptDateTime));
            }
            return(TimeSpan.Zero);
        }