public function get_download_url($product_id, $download_id)
{
wc_deprecated_function('get_download_url', '2.7', 'WC_Order_Item_Product::get_item_download_url');
return add_query_arg(array('download_file' => $product_id, 'order' => $this->get_order_key(), 'email' => urlencode($this->get_billing_email()), 'key' => $download_id), trailingslashit(home_url()));
}