    def test_makepasv_issue43285_security_disabled(self):
        """Test the opt-in to the old vulnerable behavior."""
        self.client.trust_server_pasv_ipv4_address = True
        bad_host, port = self.client.makepasv()
        self.assertEqual(
                bad_host, self.server.handler_instance.fake_pasv_server_ip)
        # Opening and closing a connection keeps the dummy server happy
        # instead of timing out on accept.
        socket.create_connection((self.client.sock.getpeername()[0], port),
                                 timeout=TIMEOUT).close()