title: Google app script to check if an email exists in domain
body: <p>We have Gsuite for education and email addresses are created by a separate department and our department hands out tickets to registered students, sometimes students can bring their friends and fake emails with our school's domain, it takes more than 3 hours to get email verification from the Registration department, we were thinking of having a google script web app where we could type in the email address and it would tell us if its real or fake. The emails should be checked on our domain only.
  We have checked the <code>User Class</code> and it only can get the current user's email address only <code>Session.getActiveUser().getEmail()</code>
  is there a function or class that can help us achieve this?</p>