In old openerp you could create order lines with concepts and without products, but since now product is a mandatory thing in lines i created a module which adds a new type of product:

type = fields.Selection(selection_add=[('ext_import', 'External import')])

We have a external partners which send us a file we import in our system as orders, but they lines in those orders aren't consumables, products or services so i decided to add an extra type of product and created a product of this type named 'import product' which i only use for this imports, the problem is when i validate the orders, the products are treated like stockable and it created procurement exceptions

How, or where should i change the code to ignore this products on stock as services are being ignored?