// change to main to run.
 public static void none(string[] args)
 {
     var person = new PersonBuilder2()
                  .Called("Sarah")
                  .WorksAs("Developer")
                  .Build();
 }
 public static PersonBuilder2 WorksAs
     (this PersonBuilder2 builder, string position)
 {
     return(builder.Do(p => p.Position = position));
 }