public String CreateCard(string walletProviderId, string walletId, Card card)
 {
     string response = "";
     Dictionary<string, string> responseMap = doRequest(GetPostURL(walletProviderId, walletId), "POST", Serializer<Card>.Serialize(card).InnerXml);
     responseMap.TryGetValue(MESSAGE, out response);
     return response;
 }
 public String UpdateCard(string walletProviderId, string walletId, string cardId, Card card)
 {
     string response = "";
     Dictionary<string, string> responseMap = doRequest(GetGetPutDeleteURL(walletProviderId, walletId, cardId), "PUT", Serializer<Card>.Serialize(card).InnerXml);
     responseMap.TryGetValue(MESSAGE, out response);
     Console.WriteLine(response);
     return response;
 }