code: def _number_xpad(self):
          
          js_path = self._device_path.replace('-event', '')
          js_chardev = os.path.realpath(js_path)
          try:
              number_text = js_chardev.split('js')[1]
          except IndexError:
              return
          try:
              number = int(number_text)
          except ValueError:
              return
          self.__device_number = number
docs: Get the number of the joystick.