docs: public static Mail buildHelloEmail() throws IOException {
      Email from = new Email("test@example.com");
      String subject = "Hello World from the SendGrid Java Library";
      Email to = new Email("test@example.com");
      Content content = new Content("text/plain", "some text here");
      // Note that when you use this constructor an initial personalization object
      // is created for you. It can be accessed via
      // mail.personalization.get(0) as it is a List object
      Mail mail = new Mail(from, subject, to, content);
      Email email = new Email("test2@example.com");
      mail.personalization.get(0).addTo(email);
  
      return mail;
    }