WooCommerce Custom Radio Button Field For Product Editor

/**
 * Snippet Name:     WooCommerce Custom Product Radio Button Field
 * Snippet Author:   ecommercehints.com
*/

// Create the custom radio metabox
add_action ('woocommerce_product_options_advanced', 'ecommercehints_custom_product_radio_metabox');
function ecommercehints_custom_product_radio_metabox() {
   echo '<div class="options_group">';
   woocommerce_wp_radio(array ( // A radio type field
      'id'                => 'custom_product_radio_metabox',
      'value'             => get_post_meta (get_the_ID(), 'custom_product_radio_metabox', true),
      'label'             => 'Radio Buttons Label',
      'description'       => 'This is the description',
      'desc_tip'          => true, // If true, place description in question mark tooltip.
     'options' => array(
       'option_1' => 'Option 1',
       'option_2' => 'Option 2',
       'option_3' => 'Option 3'
    ),
  ));
   echo '</div>';
}

// Save radio option on update
add_action ('woocommerce_process_product_meta', 'ecommercehints_save_field_on_update', 10, 2);
function ecommercehints_save_field_on_update ($id, $post) {
      update_post_meta ($id, 'custom_product_radio_metabox', $_POST['custom_product_radio_metabox']);
}

global $product;
$custom_product_radio_metabox = $product->get_meta ('custom_product_radio_metabox');
echo $custom_product_radio_metabox;