code: def process_once(self, timeout=0):
          
          log.log(logging.DEBUG - 2, "process_once()")
          sockets = self.sockets
          if sockets:
              in_, out, err = select.select(sockets, [], [], timeout)
              self.process_data(in_)
          else:
              time.sleep(timeout)
          self.process_timeout()
docs: Process data from connections once.
  
          Arguments:
  
              timeout -- How long the select() call should wait if no
                         data is available.
  
          This method should be called periodically to check and process
          incoming data, if there are any.  If that seems boring, look
          at the process_forever method.