title: how to display the upc in product page with opencart3?
body: <p>I want to display the upc in product page with opencart 3. How do I do that?</p>
  
  <p>I added the below code into my template file <code>/catalog/view/theme/default/template/product/product.twig</code>，but it doesn't work.</p>
  
  <pre><code>{% if upc %}
      {{ upc }}
  {% endif %}
  </code></pre>