def test_UIDL(self):
        """
        Test the two forms of the UIDL command.  These are just like the two
        forms of the LIST command.
        """
        p = self.pop3Server
        s = self.pop3Transport

        p.lineReceived(b"UIDL 1")
        self.assertEqual(s.getvalue(), b"+OK 0\r\n")
        s.seek(0)
        s.truncate(0)

        p.lineReceived(b"UIDL")
        self._flush()
        self.assertEqual(s.getvalue(), b"+OK \r\n1 0\r\n.\r\n")

        Test the two forms of the UIDL command.  These are just like the two
        forms of the LIST command.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/mail/test/test_pop3.py