def assertServerResponse(self, bytes, response):
        """
        Assert that when the given bytes are delivered to the ESMTP server
        instance, it responds with the indicated lines.

        @type bytes: str
        @type response: list of str
        """
        self.transport.clear()
        self.server.dataReceived(bytes)
        self.assertEqual(
            response,
            self.transport.value().splitlines())

        Assert that when the given bytes are delivered to the ESMTP server
        instance, it responds with the indicated lines.

        @type bytes: str
        @type response: list of str
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/mail/test/test_smtp.py