i have master data model contains a lot of items and i called it in product.template 
i need to make tow fields on master data model (factor, suggeted_price)
i make the factor is Float as percentage and suggested_price is computed field that equal (factor * product.template.standard_price)
​

    class cars(models.Model):
    _name = 'cars'

    @api.one
    @api.depends('factor',)
    def car_price(self):
        if self.factor:
            self.suggeted_price = self.factor * self.product.template.standard_price
        pass
    
    factor = fields.Float(string="",  required=False, )
    suggeted_price = fields.Float(string="",  required=False, compute=car_price )

i get error  'cars' object has no attribute 'product' that's actually what i expected 
i need from you to help me on how make the computed field suggested_price get it's value only when i open product form and chose it's car record then calculate itself from self.factor and self.standard_price(which on product form)