Ensure One Accordion Tab is Always Open

Hi folks, I’m using an Accordion template clone and would like to modify the Javascript so that one tab is always open. The problem is I don’t know Javascript. Can anyone help me include the correct script needed to make this happen? Thank you :pray:

var accordion = (function(){
  var $accordion = $('.add-ons_js-accordion');
  var $accordion_header = $accordion.find('.add-ons_js-accordion-header');
  var $accordion_item = $('.add-ons_js-accordion-item');
  // default settings 
  var settings = {
    // animation speed
    speed: 100,
    // close all other accordion items if true
    oneOpen: false,
  return {
    // pass configurable object literal
    init: function($settings) {
      $accordion_header.on('click', function() {
      $.extend(settings, $settings); 
      // ensure only one accordion is active if oneOpen is true
      if(settings.oneOpen && $('.add-ons_js-accordion-item.active').length > 1) {
      // reveal the active accordion bodies
      $('.add-ons_js-accordion-item.active').find('> .add-ons_js-accordion-body').show();
    toggle: function($this) {
      if(settings.oneOpen && $this[0] != $this.closest('.add-ons_js-accordion').find('> .add-ons_js-accordion-item.active > .add-ons_js-accordion-header')[0]) {
               .find('> .add-ons_js-accordion-item') 
      // show/hide the clicked accordion item

  accordion.init({ speed: 400, oneOpen: true });


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