gistfile1.php

<?php
  // Writes the appropriate #leftnav menu based on page id
  $current_page_id = get_the_ID();
  $amenities_sub_nav_pages = array(34, 63);
  if (in_array($current_page_id, $amenities_sub_nav_pages)) {
    wp_nav_menu(array(
      'container' => 'false',
      'menu' => 'amenities-sub-nav',
      'menu_id' => 'leftnav'
    ));
  }
?>