code: def set_high_water_mark(socket, config):
      
  
      if config['high_water_mark']:
          if hasattr(zmq, 'HWM'):
              # zeromq2
              socket.setsockopt(zmq.HWM, config['high_water_mark'])
          else:
              # zeromq3
              socket.setsockopt(zmq.SNDHWM, config['high_water_mark'])
              socket.setsockopt(zmq.RCVHWM, config['high_water_mark'])
docs: Set a high water mark on the zmq socket.  Do so in a way that is
      cross-compatible with zeromq2 and zeromq3.