Django: assigning a foreignKey object a value of current user
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I'm trying to override the save() method in the admin so when my publisher-users are creating their customer-users, the publisher field is automatically assigned a value of current user.

ValueError: Cannot assign "User: foo": "SimpleSubscriber.publisher" must be a "Publisher" instance.

I used this tutorial to get started: [here.][1]


  [1]: http://www.b-list.org/weblog/2008/dec/24/admin/

    def save_model(self, request, obj, form, change):
        if not change:
            obj.publisher = request.user
        obj.save()
this is the save method override.  The only users who can access the admin are publishers, and both the Publisher and SimpleSubscriber models are user models:

    class Publisher(User):
        def __unicode__(self):
            return self.get_full_name()

    class SimpleSubscriber(User):
        publisher = models.ForeignKey(Publisher)
        address = models.CharField(max_length=200)
        city = models.CharField(max_length=100)
        state = USStateField()
        zipcode = models.CharField(max_length=9)
        phone = models.CharField(max_length=10)
        date_created = models.DateField(null=True)
        sub_type = models.ForeignKey(Product)
        sub_startdate = models.DateField()
        def __unicode__(self):
            return self.last_name

What can I replace request.user with in order to assign each new SimpleSubscriber to the current publisher user?
