Show Remaining Inventory of All Variants Combined for Product

Here is the code to show the inventory quantity of each product on a collection or product page, instead of just showing the first available variants. Note, this guide will only show if inventory is below 4.

<div id="variant-inventory">
  {% assign total = 0 %}
  {%for variant in product.variants %}
    {% capture i %}{{ total | plus:variant.inventory_quantity }}{%endcapture%}
    {% assign total = i %}
  {%endfor%}
  {% unless total == '0' %}
    Only {{ total }} left
  {% endunless %}
</div>