...
> =A0if product_id =3D=3D row[0]
> =A0(price*qty) =3D=3D subtotal
...
> I don't understand why price is an unidentified variable... is the
> current code not reading it in the CSV file and giving it as an output?

You accessed the product id in the CSV by indexing into the row (row[0])
Why do expect price and qty to be different?

cheers