Customize the "Required Ticket" text for Event Espresso 4

ee_required_ticket_text.php

<?php
//* Please do NOT include the opening php tag, except of course if you're starting with a blank file

add_filter( 
  'FHEE__ticket_selector_chart_template__ticket_required_message', 
  'my_custom_message_for_required_tickets' 
);

function my_custom_message_for_required_tickets( $text ) {
  $text = 'This ticket is required.';
  return $text;
}