/// <summary>
        /// List number service
        /// </summary>
        public void ListNumberService()
        {
            var numberSearchListOptions = new NumberSearchListOptions()
            {
                CountryCode        = "US",
                AdministrativeArea = "IL",
                Locality           = "Chicago",
                Features           = new List <string> {
                    "sms"
                },
                Limit = 2
            };

            Console.WriteLine(JsonConvert.SerializeObject(numberSearchListOptions));

            try
            {
                var numberSearchList = this.service.List(numberSearchListOptions);
                Console.WriteLine("numberSearchList");
                Console.WriteLine(JsonConvert.SerializeObject(numberSearchList));
            }
            catch (TelnyxException ex)
            {
                Console.WriteLine("exception");
                Console.WriteLine(JsonConvert.SerializeObject(ex));
            }
        }
        /// <summary>
        /// List number service
        /// </summary>
        public void ListNumberService()
        {
            var listOptions = new NumberSearchListOptions();

            Console.WriteLine(JsonConvert.SerializeObject(listOptions));

            var requestOptions = new RequestOptions
            {
                ApiKey = YOURAPIKEY
            };

            Console.WriteLine(JsonConvert.SerializeObject(requestOptions));

            var numberSearchList = this.service.List(listOptions, requestOptions);

            Console.WriteLine(JsonConvert.SerializeObject(numberSearchList));
        }