code: def _verify_one(self, rsock):
          
          poller = mitogen.core.Poller()
          poller.start_receive(rsock.fileno())
          try:
              while True:
                  for fd in poller.poll():
                      return
          finally:
              poller.close()
docs: Pause until the socket `rsock` indicates readability, due to
          :meth:`_do_cork` triggering a blocking write on another thread.