using System;

public class Program

{

    public static void Main()

    {

        var accessToken = "eyJhbGciOiJSUzI1NiIsInR5cCIgOiAiSldUIiwia2lkIiA6ICJPQWc4dUJfTFYxR0NGZnBYbDZ2eTBZQXp4T0FlSjZrbjNXWUx6cFRpYWpZIn0.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.QhsJZVjH8Y3pg5o3oeKz8EDj9x3JnDmi8FlFYiILZbJRLl55h2yqN4Yb9VM_T13TIr487Kf8rL-m7XHEd33eoL5u7O37VjRZUF-M1UmF-63yGJB_B6RJcT6HAo1dJnyd1aH63hNHoUxqMQjcC6438DJRa6TZM7ZdKJcYxglj-fRBQy9_WjdX3GyfCNQyupDgbGAxNd5JpCLEEqMRLAiweP0x3TQWpfcGVz5fPAZh3ixvvtXodVOfXoOHZ4NSbxmw1fs9PDJIH3CrXarfHuPz54TnA0SIcRjSZWVu0fuK5t1UuOksXV6NIroHKVz-y8EusOspMVsAUXxHkEspvGL1ig";

        var payload = accessToken.Split('.')[1];

        var json = System.Text.Encoding.UTF8.GetString(Convert.FromBase64String(payload+ new string('=', payload.Length % 4)));

        Console.WriteLine(json);

    }

}