human
I wrote the below code

    import pyflic
    host = config.get(CONF_HOST)
    port = config.get(CONF_PORT)
    discovery = config.get(CONF_DISCOVERY)
    try:
        client = pyflic.FlicClient(host, port)
    except ConnectionRefusedError:
        _LOGGER.error('Failed    to    connect    to    flic    server')
        return
    def new_button_callback(address):
        'Set    up    newly    verified    button    as    device    in    Home    Assistant.'
        setup_button(hass, config, add_entities, client, address)
    client.on_new_verified_button = new_button_callback
    if discovery:
        start_scanning(config, add_entities, client)
    hass.bus.listen_once(EVENT_HOMEASSISTANT_STOP, (lambda event: client.close()))
    threading.Thread(target=client.handle_events).start()
    def get_info_callback(items):
        'Add    entities    for    already    verified    buttons.'
        addresses = (items['bd_addr_of_verified_buttons'] or [])
        for address in addresses:
            setup_button(hass, config, add_entities, client, address)
    client.get_info(get_info_callback)

What's a good function header?

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

def setup_platform(hass, config, add_entities, discovery_info=None):