private static Request BuildReadRequest(ReadMobileOptions options, ITwilioRestClient client)
 {
     return(new Request(
                HttpMethod.Get,
                Rest.Domain.Api,
                "/2010-04-01/Accounts/" + (options.PathAccountSid ?? client.AccountSid) + "/AvailablePhoneNumbers/" + options.PathCountryCode + "/Mobile.json",
                queryParams: options.GetParams()
                ));
 }