def test_ControlL(self):
        """
        CTRL+L is generally used as a redraw-screen command in terminal
        applications.  Manhole doesn't currently respect this usage of it,
        but it should at least do something reasonable in response to this
        event (rather than, say, eating your face).
        """
        # Start off with a newline so that when we clear the display we can
        # tell by looking for the missing first empty prompt line.
        self._testwrite(b"\n1 + 1")
        yield self.recvlineClient.expect(br"\+ 1")
        self._assertBuffer([b">>> ", b">>> 1 + 1"])

        self._testwrite(manhole.CTRL_L + b" + 1")
        yield self.recvlineClient.expect(br"1 \+ 1 \+ 1")
        self._assertBuffer([b">>> 1 + 1 + 1"])

        CTRL+L is generally used as a redraw-screen command in terminal
        applications.  Manhole doesn't currently respect this usage of it,
        but it should at least do something reasonable in response to this
        event (rather than, say, eating your face).
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/conch/test/test_manhole.py