Hi,

Here the template name for the report is "report_saledetails" , there is a corresponding abstract model created for this reporting template named as "report.point_of_sale.report_saledetails" in this 
model there is a function named as "get_sale_details" , some datas are passed in the return of this function on line 1437 as a dictionary, inside it there is another listdict with the key as "products" , 
so in the template they loop products list dict as "line" and take the line['product_name'] and line['code']

Regards