'Setup timeout handler for detecting \'no-activity\'
and start polling.'

def start(self):

    fail_timer = self.ioloop.add_timeout(self.TIMEOUT, self.on_timeout)
    self.addCleanup(self.ioloop.remove_timeout, fail_timer)
    self.ioloop.start()
    self.ioloop._poller.activate_poller.assert_called_once_with()
    self.ioloop._poller.deactivate_poller.assert_called_once_with()
