def METHOD_NAME(self):
    data = {"item1": json.dumps({"ref": "0000000000000000000000000"})}
    headers = [
        ("Content-Type", "application/x-www-form-urlencoded"),
        ("If-Match", self.item_etag),
    ]
    r = self.test_client.patch(self.item_id_url, data=data, headers=headers)
    response = json.loads(r.get_data().decode())
    self.assertTrue("_links" not in response)