How can I filter queryset by type of a field

Question

I use mezzanine. It has model:

class AssignedKeyword(Orderable):
    """
    A ``Keyword`` assigned to a model instance.
    """

    keyword = models.ForeignKey("Keyword", related_name="assignments")
    content_type = models.ForeignKey("contenttypes.ContentType")
    object_pk = models.IntegerField()
    content_object = GenericForeignKey("content_type", "object_pk")

    class Meta:
        order_with_respect_to = "content_object"

    def __unicode__(self):
        return unicode(self.keyword)

I want to get all unique AssignedKeyword model instances, where type of content_object field is Post . How can I filter queryset by type of a field?

Answer 1

答案很简单：

AssignedKeyword.objects.filter(content_type=ContentType.objects.get(name='Product'))