def test_opCode(self):
        """
        L{dns._EDNSMessage.opCode} defaults to L{dns.OP_QUERY} and can be
        overridden in the constructor.
        """
        self._verifyConstructorArgument(
            'opCode', defaultVal=dns.OP_QUERY, altVal=dns.OP_STATUS)

        L{dns._EDNSMessage.opCode} defaults to L{dns.OP_QUERY} and can be
        overridden in the constructor.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/names/test/test_dns.py