Tags in product properties

Product.php

<?php

class Product extends ProductCore{

    public static function getProductProperties($id_lang, $row, Context $context = null)
    {
        $row = parent::getProductProperties($id_lang, $row, $context);
        if (is_array($row) && isset($row['id_product'])) {
            $usetax = Tax::excludeTaxeOption();
    	    $cache_key = $row['id_product'].'-'.$row['id_product_attribute'].'-'.$id_lang.'-'.(int)$usetax;
            self::$producPropertiesCache[$cache_key]['tags'] = Tag::getProductTags($row['id_product']);
            $row = self::$producPropertiesCache[$cache_key];
        }
        return $row;
    }
}