public void Run(params string[] args)
        {
            Tenant t = PhoneSystem.Root.GetTenants()[0];
            DN     e = null;

            foreach (DN dn in t.GetDN())
            {
                if (dn.Number == "108")
                {
                    e = dn;
                }
            }
            PhoneBookEntry a = t.CreatePhoneBookEntry();

            a.FirstName   = "TenantFN";
            a.LastName    = "TenantLN";
            a.PhoneNumber = "54321";
            a.Save();
            a             = e.CreatePhoneBookEntry();
            a.FirstName   = "ExtFN";
            a.LastName    = "ExtLN";
            a.PhoneNumber = "7890";
            a.Save();
            Thread.Sleep(2000);
            t.Refresh();
            e.Refresh();
            foreach (PhoneBookEntry pbe in t.GetPhoneBookEntries())
            {
                System.Console.WriteLine(pbe.ToString());
            }
            foreach (PhoneBookEntry pbe in e.GetPhoneBookEntries())
            {
                System.Console.WriteLine(pbe.ToString());
            }
        }