code: async def close(self, code: int=1000, message: bytes=b'') -> None:
          
          if isinstance(message, str):
              message = message.encode('utf-8')
          try:
              await self._send_frame(
                  PACK_CLOSE_CODE(code) + message, opcode=WSMsgType.CLOSE)
          finally:
              self._closing = True
docs: Close the websocket, sending the specified code and message.