private async Task<StreetData> GetSingleAddressAsync(string postalCode, string endPointName)
 {
     var wcfClient = new StreetLookupClient(endPointName);
     var sd = await wcfClient.GetStreetAsync(postalCode);
     return sd;
 }
 private StreetData GetSingleAddress(string postalCode, string endPointName)
 {
     var wcfClient = new StreetLookupClient(endPointName);
     return wcfClient.GetStreet(postalCode);
 }