def METHOD_NAME(self):
    """
    Retrieves the speed of fan as a percentage of full speed
    Returns:
        An integer, the percentage of full fan speed, in the range 0 (off)
             to 100 (full speed)
    """
    speed = 44
    rv = self.__get_attr_value(self.__rpm)
    if rv != 'ERR':
        speed = int(
            rv) * 100 // (MAX_PSU_FAN_RPM if self.__psu_fan else MAX_FAN_RPM)
    return speed