def get_available_sensors(cls, types=None):
        """
            Return all available sensors.

            :param list types: the type of the sensor to look for.
                               If types is None it will search for all available types.

            :returns: a list of sensor instances.
            :rtype: list

        """
        if not types:
            types = cls.TYPE_NAMES.keys()
        is_sensor = lambda s: any(s.startswith(hex(x)[2:]) for x in types)  # noqa
        return [
            cls(cls.RESOLVE_TYPE_STR[s[:2]], s[3:])
            for s in os.listdir(cls.BASE_DIRECTORY)
            if is_sensor(s)
        ]
Return all available sensors.

            :param list types: the type of the sensor to look for.
                               If types is None it will search for all available types.

            :returns: a list of sensor instances.
            :rtype: list