我想改变感谢你的消息，如果付款方式是chosed，我已经实现了这一点，工作，但仍然不知道需要这一行在下面的代码我需要它吗？

add_filter('woocommerce_thankyou_order_received_text', 'woo_change_order_received_text', 20, 2 );
function woo_change_order_received_text( $str, $order ) {

$order = wc_get_order( $order_id ); // do i need this line, it works without it do i need it ????????

    if( 'bacs' == $order->get_payment_method() ) {
    $new_str = $str . '<br><br><span style="display:block;font-weight:bold; text-align:center"> Please after your payment is done make sure to visit </span><br>';
    return $new_str;
    }
    return $str;
}

我需要这条线，它没有它也能工作，我需要它吗？

$order = wc_get_order( $order_id );