I have a selection field

award = fields.Selection([
    ('awarded', 'Adjudicado'),
    ('not_awarded', 'No Adjudicado'),
],string="Adjudicacion", required="True")

And I have this function

def button_confirm(self):
        res = super(PurchaseOrder,self).button_confirm()
        if res.award == res.not_awarded:
            raise ValidationError("No puedes confirmar este pedido")

What I want to do is that when the user makes a budget request in the purchase order, if the user has "not_awarded" selected and then confirms the order, I throw an error that he has to have "awarded" selected

In the end I have this error.

AttributeError: 'bool' object has no attribute 'award'