How to use the homeassistant.const.CONF_USERNAME function in homeassistant

async def async_setup(hass, config):
    """Set up the Eight Sleep component."""

    conf = config.get(DOMAIN)
    user = conf.get(CONF_USERNAME)
    password = conf.get(CONF_PASSWORD)
    partner = conf.get(CONF_PARTNER)

    if hass.config.time_zone is None:
        _LOGGER.error("Timezone is not set in Home Assistant.")
        return False

    timezone = hass.config.time_zone

    eight = EightSleep(user, password, timezone, partner, None, hass.loop)

    hass.data[DATA_EIGHT] = eight

    # Authenticate, build sensors
    success = await eight.start()
    if not success:

async def async_setup_platform(
        hass, config, async_add_entities, discovery_info=None):
    """Set up the iRobot Roomba vacuum cleaner platform."""
    from roomba import Roomba
    if PLATFORM not in hass.data:
        hass.data[PLATFORM] = {}

    host = config.get(CONF_HOST)
    name = config.get(CONF_NAME)
    username = config.get(CONF_USERNAME)
    password = config.get(CONF_PASSWORD)
    certificate = config.get(CONF_CERT)
    continuous = config.get(CONF_CONTINUOUS)

    roomba = Roomba(
        address=host, blid=username, password=password, cert_name=certificate,
        continuous=continuous)
    _LOGGER.debug("Initializing communication with host %s", host)

    try:
        with async_timeout.timeout(9):
            await hass.async_add_job(roomba.connect)
    except asyncio.TimeoutError:
        raise PlatformNotReady

    roomba_vac = RoombaVacuum(name, roomba)

HA_SWITCH = 'switch'
HA_SENSOR = 'sensor'

SIGNAL_DELETE_ENTITY = 'meross_delete'
SIGNAL_UPDATE_ENTITY = 'meross_update'

DEFAULT_SCAN_INTERVAL = timedelta(seconds=10)

CONF_MEROSS_DEVICES_SCAN_INTERVAL = 'meross_devices_scan_interval'
DEFAULT_MEROSS_DEVICES_SCAN_INTERVAL = timedelta(minutes=15)

CONFIG_SCHEMA = vol.Schema({
    DOMAIN: vol.Schema({
        vol.Required(CONF_PASSWORD): cv.string,
        vol.Required(CONF_USERNAME): cv.string,

        vol.Optional(CONF_SCAN_INTERVAL, default=DEFAULT_SCAN_INTERVAL): cv.time_period,
        vol.Optional(CONF_MEROSS_DEVICES_SCAN_INTERVAL, default=DEFAULT_MEROSS_DEVICES_SCAN_INTERVAL): cv.time_period,
    })
}, extra=vol.ALLOW_EXTRA)


# ----------------------------------------------------------------------------------------------------------------------
#
# ASYNC SETUP
#
# ----------------------------------------------------------------------------------------------------------------------


async def async_setup(hass, config):

def __init__(self, config):
        """Initialize the scanner."""
        self.last_results = None
        self.url = config[CONF_URL]
        self.username = config[CONF_USERNAME]
        self.password = config[CONF_PASSWORD]
        self.rssi_min = config.get(CONF_RSSI)
        self.scan_interval = config[CONF_SCAN_INTERVAL]
        self.last_results = []

        # NOTE: Padavan httpd will even don't check HTTP authorization header if multiple devices connected, if will
        # show "You cannot Login unless logout another user first." page instead with mac/ip of authorized device.
        r = self._request()
        self.success_init = True if 'text' in r or r['error_id'] == 'multiple' else False

        if self.success_init:
            _LOGGER.info('Successfully connected to Padavan-based router')
            if 'error_id' in r:
                _LOGGER.info('But %s', r['error_msg'])
        else:
            _LOGGER.error('Failed to connect to Padavan-based router: %s', r['error_msg'])

DEFAULT_PORT = 1234
DEFAULT_USERNAME = "admin"
Device = namedtuple("device", ["netio", "entities"])
DEVICES = {}

MIN_TIME_BETWEEN_SCANS = timedelta(seconds=10)

REQ_CONF = [CONF_HOST, CONF_OUTLETS]

URL_API_NETIO_EP = "/api/netio/{host}"

PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
    {
        vol.Required(CONF_HOST): cv.string,
        vol.Required(CONF_PORT, default=DEFAULT_PORT): cv.port,
        vol.Required(CONF_USERNAME, default=DEFAULT_USERNAME): cv.string,
        vol.Required(CONF_PASSWORD): cv.string,
        vol.Optional(CONF_OUTLETS): {cv.string: cv.string},
    }
)


def setup_platform(hass, config, add_entities, discovery_info=None):
    """Set up the Netio platform."""

    host = config.get(CONF_HOST)
    username = config.get(CONF_USERNAME)
    password = config.get(CONF_PASSWORD)
    port = config.get(CONF_PORT)

    if not DEVICES:
        hass.http.register_view(NetioApiView)

VALID_TARGET_HEAT = vol.All(vol.Coerce(int), vol.Clamp(min=0, max=100))
VALID_DURATION = vol.All(vol.Coerce(int), vol.Clamp(min=0, max=28800))

SERVICE_EIGHT_SCHEMA = vol.Schema(
    {
        ATTR_ENTITY_ID: cv.entity_ids,
        ATTR_TARGET_HEAT: VALID_TARGET_HEAT,
        ATTR_HEAT_DURATION: VALID_DURATION,
    }
)

CONFIG_SCHEMA = vol.Schema(
    {
        DOMAIN: vol.Schema(
            {
                vol.Required(CONF_USERNAME): cv.string,
                vol.Required(CONF_PASSWORD): cv.string,
                vol.Optional(CONF_PARTNER, default=DEFAULT_PARTNER): cv.boolean,
            }
        )
    },
    extra=vol.ALLOW_EXTRA,
)


async def async_setup(hass, config):
    """Set up the Eight Sleep component."""

    conf = config.get(DOMAIN)
    user = conf.get(CONF_USERNAME)
    password = conf.get(CONF_PASSWORD)
    partner = conf.get(CONF_PARTNER)

def setup_platform(hass, config, add_entities, discovery_info=None):
    """Set up the Deluge switch."""
    from deluge_client import DelugeRPCClient

    name = config.get(CONF_NAME)
    host = config.get(CONF_HOST)
    username = config.get(CONF_USERNAME)
    password = config.get(CONF_PASSWORD)
    port = config.get(CONF_PORT)

    deluge_api = DelugeRPCClient(host, port, username, password)
    try:
        deluge_api.connect()
    except ConnectionRefusedError:
        _LOGGER.error("Connection to Deluge Daemon failed")
        raise PlatformNotReady

    add_entities([DelugeSwitch(deluge_api, name)])

cv.ensure_list, [vol.In(SENSORS)]
        )
    }
)

SERVICE_TRIGGER_SCHEMA = vol.Schema({vol.Required(CONF_NAME): cv.string})

SERVICE_SAVE_VIDEO_SCHEMA = vol.Schema(
    {vol.Required(CONF_NAME): cv.string, vol.Required(CONF_FILENAME): cv.string}
)

CONFIG_SCHEMA = vol.Schema(
    {
        DOMAIN: vol.Schema(
            {
                vol.Required(CONF_USERNAME): cv.string,
                vol.Required(CONF_PASSWORD): cv.string,
                vol.Optional(
                    CONF_SCAN_INTERVAL, default=DEFAULT_SCAN_INTERVAL
                ): cv.time_period,
                vol.Optional(CONF_BINARY_SENSORS, default={}): BINARY_SENSOR_SCHEMA,
                vol.Optional(CONF_SENSORS, default={}): SENSOR_SCHEMA,
                vol.Optional(CONF_OFFSET, default=1): int,
                vol.Optional(CONF_MODE, default=""): cv.string,
            }
        )
    },
    extra=vol.ALLOW_EXTRA,
)


def setup(hass, config):

REQUIREMENTS = ['myusps==1.3.2']

_LOGGER = logging.getLogger(__name__)

DOMAIN = 'usps'
DATA_USPS = 'data_usps'
MIN_TIME_BETWEEN_UPDATES = timedelta(minutes=30)
COOKIE = 'usps_cookies.pickle'
CACHE = 'usps_cache'
CONF_DRIVER = 'driver'

USPS_TYPE = ['sensor', 'camera']

CONFIG_SCHEMA = vol.Schema({
    DOMAIN: vol.Schema({
        vol.Required(CONF_USERNAME): cv.string,
        vol.Required(CONF_PASSWORD): cv.string,
        vol.Optional(CONF_NAME, default=DOMAIN): cv.string,
        vol.Optional(CONF_DRIVER): cv.string
    }),
}, extra=vol.ALLOW_EXTRA)


def setup(hass, config):
    """Use config values to set up a function enabling status retrieval."""
    conf = config[DOMAIN]
    username = conf.get(CONF_USERNAME)
    password = conf.get(CONF_PASSWORD)
    name = conf.get(CONF_NAME)
    driver = conf.get(CONF_DRIVER)

    import myusps

_LOGGER = logging.getLogger(__name__)

COVER_FEATURES = SUPPORT_OPEN | SUPPORT_CLOSE | SUPPORT_SET_POSITION
DEVICE_CLASS = "window"

ATTR_REQUEST_POSITION = "request_position"
NOTIFICATION_ID = "brunt_notification"
NOTIFICATION_TITLE = "Brunt Cover Setup"
ATTRIBUTION = "Based on an unofficial Brunt SDK."

CLOSED_POSITION = 0
OPEN_POSITION = 100

PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
    {vol.Required(CONF_USERNAME): cv.string, vol.Required(CONF_PASSWORD): cv.string}
)


def setup_platform(hass, config, add_entities, discovery_info=None):
    """Set up the brunt platform."""

    username = config[CONF_USERNAME]
    password = config[CONF_PASSWORD]

    bapi = BruntAPI(username=username, password=password)
    try:
        things = bapi.getThings()["things"]
        if not things:
            _LOGGER.error("No things present in account.")
        else:
            add_entities(