where is admin footer?


hi im working on my new wordpress website. and i wanted to add custom order status in my woocommerce order status and i found this code:-

function custom_bulk_admin_footer() { global $ post_type;

        if ( $  post_type == 'shop_order' ) {             ?>                 <script type="text/javascript">                     jQuery(document).ready(function() {                         jQuery('<option>').val('mark_invoiced').text('<?php _e( 'Mark invoiced', 'textdomain' ); ?>').appendTo("select[name='action']");                         jQuery('<option>').val('mark_invoiced').text('<?php _e( 'Mark invoiced', 'textdomain' ); ?>').appendTo("select[name='action2']");                        });                 </script>             <?php         }     } 

the question is , where should i put the code ? should i put it in my theme function.php ? or put it in admin_footer? if so can someone navigate me to the admin_footer section?