Fixed an undefined variable and clarified the purpose of a test.

class ModifyingSaveData(models.Model):

    data = models.IntegerField(null=True)

    def save(self):

        "A save method that modifies the data in the object"

    def save(self, *args, **kwargs):

        """

        A save method that modifies the data in the object.

        Verifies that a user-defined save() method isn't called when objects

        are deserialized (#4459).

        """

        self.data = 666

        super(ModifyingSaveData, self).save(raw)

        super(ModifyingSaveData, self).save(*args, **kwargs)

# Tests for serialization of models using inheritance.

# Regression for #7202, #7350

    def __len__(self):

        return self.data