docs: def setup_handler(self, io_loop):
  		""" :meth:`.WIOLoopServiceHandler.setup_handler` implementation.
  		If :class:`.WNativeSocketDirectIOHandler` is used as a io-handler, then socket object is saved
  		to this handler before loop starting
  
  		:param io_loop: io_loop to use
  		:return: None
  		"""
  
  		if self.server_mode() is True:
  			s = self.transport().server_socket(self.config())
  		else:
  			s = self.transport().client_socket(self.config())
  
  		io_handler = self.io_handler()
  		if isinstance(io_handler, WNativeSocketDirectIOHandler) is True:
  			io_handler.transport_socket(s)
  		io_loop.add_handler(s.fileno(), io_handler.handler_fn, io_loop.READ)