static void Main(string[] args)
        {
            WriteHeading();
            WriteLine();
            var discoveryDocument = IdentityClient.Discovery().Result;

            // discovery doc
            PrintDiscoveryDocument(discoveryDocument);
            WriteLine();
            // token request
            var tokenResponse = IdentityClient.RequestToken(discoveryDocument).Result;

            WriteLine();
            PrintTokenResponse(tokenResponse);
            WriteLine();
            // API CALL
            var apiCallResponse = IdentityClient.CallApi(tokenResponse).Result;

            PrintApiCallResponse(apiCallResponse);