def METHOD_NAME(self):
    """
    Error case: the client is asking for a category that does not exist
    """
    # Act like the ES client would when we attempt to get a non-existent document
    with mock.patch.object(ES_CLIENT, "get", side_effect=NotFoundError):
        response = self.client.get("/api/v1.0/categories/43/", follow=True)
    # The client received a standard NotFound response
    self.assertEqual(response.status_code, 404)