function onFormSubmit(e) MailApp.sendEmail

function onFormSubmit(e) {
  var timestamp = e.values[0];
  var name = e.values[1];
  var age = e.values[2]; 
  var submitter = e.values[3]; 

  MailApp.sendEmail("email_username", "form submitted", name + ", age " + age + " submitted by " + submitter + " on " + timestamp + ".")
}