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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_app_content_types(self):
 """ Return a list of all content_types for this app. """

        # Import this here to silence RemovedInDjango19Warning. See #15
        from django.contrib.contenttypes.models import ContentType

        return [ContentType.objects.get_for_model(c) for c
                in self.get_app_model_classes()]