@classmethod
def _get_sensors_fan(cls, chassis):
    """Get fan sensors reading.

        :param chassis: Redfish `chassis` object
        :returns: returns a dict of sensor data.
        """
    sensors = {}
    for fan in chassis.thermal.fans:
        sensor = cls._sensor2dict(fan, 'identity', 'max_reading_range',
            'min_reading_range', 'reading', 'reading_units',
            'serial_number', 'physical_context')
        sensor.update(cls._sensor2dict(fan.status, 'state', 'health'))
        unique_name = '%s@%s' % (fan.identity, chassis.identity)
        sensors[unique_name] = sensor
    return sensors
