Appengine form script

Hi, Basically, I need an Google Appengine form PHP script that post input data in HTML to an emailadres. - Form input fields: name, lastname, address, postalcode, city, email. - Opt-in checkbox - All fields and checkbox are required - Validation on emailaddress - Succes page I only need the PHP script, the form is already done. Many thanks in advance! Cheers, --------------- This is the code I have so far: <?php require_once 'google/appengine/api/mail/[login to view URL]'; use google\appengine\api\mail\Message; $message_body = "....."; $mail_options = [ 'sender' => '', 'to' => '', 'subject' => 'Subject', 'textBody' => $message_body ]; try { $message = new Message($mail_options); $message->send(); } catch (InvalidArgumentException $e) { echo "not send"; }?>