Hello everybody!

I have created 2 classes which are really similar:
class A(models.Model):
    _name = 'product.template'
    _inherit = 'product.template'
    file = fields.Binary(_('File'), required=False)
   
class B(models.Model):
    _name = "product.template"
    _inherit = 'product.template'
....   
...
my_file = self.env['product.template'].file

I want to access the file field of class A from class B but I always get value none/False eventhough i have a file uploaded. I tried with other custom fields also but what I get is nothing.
Is there a way to access fields from the other classes of the inherited product.template?

Thanks a lot in advance!