On     website_sale\views\templates.xml

<template id="variants">

    <t t-foreach="product.attribute_line_ids.sorted(key=lambda x: x.attribute_id.sequence)" t-as="variant_id">

        <li t-if="len(variant_id.value_ids) > 1">

            <strong t-field="variant_id.attribute_id.name"/>

            //output example: Size

            <t t-foreach="variant_id.value_ids" t-as="value_id">

                <span t-field="value_id.name"/> 

                    //output example: Small

            <strong t-field="variant_id.attribute_id.name"/>

            //output example: Color

            <t t-foreach="variant_id.value_ids" t-as="value_id">

                <span t-field="value_id.name"/> 

                    //output example: Blue              

I want to have the barcode and internal reference along with "Small" and "Blue".

In other words, how do I encounter the specific product_product from one product_attribute_value of a given product_template?