code: def _handle_events(self, fd: int, events: int) -> None:
          
          action = 0
          if events & ioloop.IOLoop.READ:
              action |= pycurl.CSELECT_IN
          if events & ioloop.IOLoop.WRITE:
              action |= pycurl.CSELECT_OUT
          while True:
              try:
                  ret, num_handles = self._multi.socket_action(fd, action)
              except pycurl.error as e:
                  ret = e.args[0]
              if ret != pycurl.E_CALL_MULTI_PERFORM:
                  break
          self._finish_pending_requests()
docs: Called by IOLoop when there is activity on one of our
          file descriptors.