Populate a variant metafield with the price of a product at the point the product is created

Thanks Paul. Gave this a go:

{% for variants_item in product.variants %}
{% if forloop.first %}
{
“amount”: {{ variants_item.price }},
“currency_code”: “EUR”
}
{% endif %}
{% endfor %}

… but nothing seems to happen. No errors, but nothing updates.

Here’s the current flow. I’m not sure where to go from here. Any advice would be greatly appreciated.