human
I wrote the below code

    global KNXTUNNEL
    from knxip.ip import KNXIPTunnel
    from knxip.core import KNXException, parse_group_address
    host = config[DOMAIN].get(CONF_HOST)
    port = config[DOMAIN].get(CONF_PORT)
    if (host == '0.0.0.0'):
        _LOGGER.debug('Will    try    to    auto-detect    KNX/IP    gateway')
    KNXTUNNEL = KNXIPTunnel(host, port)
    try:
        res = KNXTUNNEL.connect()
        _LOGGER.debug('Res    =    %s', res)
        if (not res):
            _LOGGER.error('Could    not    connect    to    KNX/IP    interface    %s', host)
            return False
    except KNXException as ex:
        _LOGGER.exception("Can't    connect    to    KNX/IP    interface:    %s", ex)
        KNXTUNNEL = None
        return False
    _LOGGER.info('KNX    IP    tunnel    to    %s:%i    established', host, port)
    descriptions = load_yaml_config_file(os.path.join(os.path.dirname(__file__), 'services.yaml'))
    def received_knx_event(address, data):
        'Process    received    KNX    message.'
        if (len(data) == 1):
            data = data[0]
        hass.bus.fire('knx_event', {'address': address, 'data': data})
    for listen in config[DOMAIN].get(CONF_LISTEN):
        _LOGGER.debug('Registering    listener    for    %s', listen)
        try:
            KNXTUNNEL.register_listener(parse_group_address(listen), received_knx_event)
        except KNXException as knxexception:
            _LOGGER.error("Can't    register    KNX    listener    for    address    %s    (%s)", listen, knxexception)
    hass.bus.listen_once(EVENT_HOMEASSISTANT_STOP, close_tunnel)
    def handle_group_write(call):
        'Bridge    knx_frame_send    events    to    the    KNX    bus.'
        addrlist = call.data.get('address')
        knxdata = call.data.get('data')
        knxaddrlist = []
        for addr in addrlist:
            try:
                _LOGGER.debug('Found    %s', addr)
                knxaddr = int(addr)
            except ValueError:
                knxaddr = None
            if (knxaddr is None):
     ...

What's a good function header?
 ... Here's a good function header?
assistant
#Here's a good function header.

def setup(hass, config):