@staticmethod
def _entity_sensor_scale_to_exponent(sensor_scale):
    """
        sensor_scale is an integer index that refers to an exponent applied to entSensorValue.  The sensor_exponent
        comes from the Cisco definitions.

        Args:
            sensor_scale(int): entSensorScale value
        Returns:
            int: signed integer exponent to be applied to entSensorValue to normalize
        """
    sensor_exponent = [u'-24', u'-21', u'-18', u'-15', u'-12', u'-9', u'-6',
        u'-3', u'0', u'3', u'6', u'9', u'12', u'15', u'18', u'21', u'24']
    return int(sensor_exponent[sensor_scale - 1])
