private void RetrieveUrls(QueryServiceClient queryServiceClient, Region region)
        {
            WSU.MainServiceLogger.Info("Retrieve Urls for Region: " + ApexConsumer.ToString(region));
            UrlSet urlSet = queryServiceClient.RetrieveUrlsForContext(
                SessionHeader,
                new SingleRegionContext
            {
                BusinessUnitEntityKey = region.BusinessUnitEntityKey,
                RegionEntityKey       = region.EntityKey
            });

            if (urlSet == null)
            {
                throw new Exception("Retrieve Urls failed with a null result for Region: " + ApexConsumer.ToString(region));
            }
            else
            {
                WSU.MainServiceLogger.Debug("Retrieve Urls completed successfully for Region: " + ApexConsumer.ToString(region));
                RegionUrlSets.Add(region.EntityKey, urlSet);
            }
        }