WooCommerce - Show custom message in cart totals

<?php
  // WooCommerce - Show custom message in cart totals
  add_action( 'woocommerce_cart_totals_after_shipping', 'custom_cutting_message', 10 );
  function custom_cutting_message() {
    $cart = WC()->cart;
    $subtotal = $cart->get_subtotal();
    if( $subtotal > 450 ) {
      return;
    }
    // loop over $cart items
    $includes_delivery_roll_cutting_class = false;
    foreach ( WC()->cart->get_cart() as $cart_item_key => $cart_item ) {
      $product = $cart_item['data'];
      $shipping_class = $cart_item['data']->get_shipping_class(); // product shipping class slug
      if( 'delivery-roll-cutting' == $shipping_class ) {
        $includes_delivery_roll_cutting_class = true;
        break;
      }
    }
    if( $includes_delivery_roll_cutting_class ) {
      print '<tr><th colspan="2" class="shipping_message">This includes cutting the roll.<br>Spend over £450 for free roll cutting and delivery.</th></tr>'.PHP_EOL;
    } else {
      print '<tr><th colspan="2" class="shipping_message">Spend over £450 for free delivery.</th></tr>'.PHP_EOL;
    }
  } // end function