Using NodaTime Period class to serialize/deserialize ISO 8601 duration

PeriodSerialization.cs

using System;
using System.Text;
using System.IO;
using Newtonsoft.Json;
using NodaTime;
using NodaTime.Serialization.JsonNet;


namespace FormattingUtils
{
    public static class Extensions
    {

        public static Period ToPeriod(this string input)
        {
            var js = JsonSerializer.Create(new JsonSerializerSettings());
            js.ConfigureForNodaTime(DateTimeZoneProviders.Tzdb);
            var quoted = String.Concat(@"""", input, @"""");
            return js.Deserialize<Period>(new JsonTextReader(new StringReader(quoted)));
        }

    }

    class Program
    {
        static void Main(string[] args)
        {
            // 15 years
            var p = "P15Y".ToPeriod();
            Console.WriteLine(String.Format("{0} years is represented as P15Y", p.Years));

            // 6 months
            Console.WriteLine("6 months is represented as " +  Period.FromMonths(6).ToString());

            Console.ReadLine();
        }

    }
}