def test_sendEOF(self):
        """
        Test that channel EOF messages are sent in the right format.
        """
        channel = TestChannel()
        self._openChannel(channel)
        self.conn.sendEOF(channel)
        self.assertEqual(self.transport.packets,
                [(connection.MSG_CHANNEL_EOF, b'\x00\x00\x00\xff')])
        channel.localClosed = True
        self.conn.sendEOF(channel)
        self.assertEqual(self.transport.packets,
                [(connection.MSG_CHANNEL_EOF, b'\x00\x00\x00\xff')])

        Test that channel EOF messages are sent in the right format.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_connection.py