To import a product with variants using a xls/csv sheet I know I can use a colom 'attribute values' and place the variants comma separated like L,S,M. This wil make the product.template with 3 variants.

But now I want to do a import where every attribute value is on it own line in the sheet. In this example it would be 3 lines with each it's own value. The result should be one product.template with 3 variant as above.

The import sheet can look like if you do an export of a product.template and his variants. Every variant has it's own line and not on one line with comma separated values for the attribute.

I was not able to do this. Everytime I end up with several product.templates. Who knows how to take care of this?

Odoo V13