How to use the appdaemon.stream.RequestHandlerException function in appdaemon

if "namespace" not in data:
            raise RequestHandlerException('invalid namespace')

        if "service" not in data:
            raise RequestHandlerException('invalid service')
        else:
            service = data['service']

        if "domain" not in data:
            d, s = service.split("/")
            if d and s:
                domain = d
                service = s
            else:
                raise RequestHandlerException('invalid domain')
        else:
            domain = data['domain']

        if "data" not in data:
            service_data = {}
        else:
            service_data = data['data']

        return await self.AD.services.call_service(data['namespace'], domain, service, service_data)

async def call_service(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        if "namespace" not in data:
            raise RequestHandlerException('invalid namespace')

        if "service" not in data:
            raise RequestHandlerException('invalid service')
        else:
            service = data['service']

        if "domain" not in data:
            d, s = service.split("/")
            if d and s:
                domain = d
                service = s
            else:
                raise RequestHandlerException('invalid domain')
        else:
            domain = data['domain']

        if "data" not in data:
            service_data = {}
        else:

async def listen_event(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        if "namespace" not in data:
            raise RequestHandlerException('invalid namespace')

        if "event" not in data:
            raise RequestHandlerException('invalid event')

        handle = data.get('handle', uuid.uuid4().hex)

        if handle in self.subscriptions['event']:
            raise RequestHandlerException('handle already exists')

        self.subscriptions['event'][handle] = {
            "namespace": data['namespace'],
            "event": data['event']
        }

        return handle

async def hello(self, data):
        if "client_name" not in data:
            raise RequestHandlerException('client_name required')

        if self.AD.http.password is None:
            self.authed = True

        if not self.authed:
            await self._auth_data(data)

        if not self.authed:
            raise RequestHandlerException('authorization failed')

        self.access.info("New client %s connected", data["client_name"])
        response_data = {
            "version": utils.__version__
        }

        return response_data

async def get_state(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        namespace = data.get('namespace', None)
        entity_id = data.get('entity_id', None)

        if entity_id is not None and namespace is None:
            raise RequestHandlerException('entity_id cannoy be set without namespace')

        return self.AD.state.get_entity(namespace, entity_id)

async def fire_event(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        if "namespace" not in data:
            raise RequestHandlerException('invalid namespace')

        if "event" not in data:
            raise RequestHandlerException('invalid event')

        event_data = data.get('data', {})

        return await self.AD.events.fire_event(data['namespace'], data['event'], **event_data)

async def listen_event(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        if "namespace" not in data:
            raise RequestHandlerException('invalid namespace')

        if "event" not in data:
            raise RequestHandlerException('invalid event')

        handle = data.get('handle', uuid.uuid4().hex)

        if handle in self.subscriptions['event']:
            raise RequestHandlerException('handle already exists')

        self.subscriptions['event'][handle] = {
            "namespace": data['namespace'],
            "event": data['event']
        }

        return handle

if not hasattr(self, msg['request_type']):
            return await self._response_error(msg, 'unavailable request')

        fn = getattr(self, msg['request_type'])

        if not callable(fn):
            return await self._response_error(msg, 'uncallable request')

        request_data = msg.get('data', {})
        request_id = msg.get('request_id', None)

        try:
            data = await fn(request_data)
            if data is not None or request_id is not None:
                return await self._response_success(msg, data)
        except RequestHandlerException as e:
            return await self._response_error(msg, str(e))
        except Exception as e:
            await self._response_error(msg, "Unknown error occured, check AppDaemon logs: {}".format(str(e)))
            raise

async def cancel_listen_state(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        if "handle" not in data:
            raise RequestHandlerException('invalid handle')

        if data['handle'] not in self.subscriptions['state']:
            raise RequestHandlerException('invalid handle')

        del self.subscriptions['state'][data['handle']]

        return True

async def listen_state(self, data):
        if not self.authed:
            raise RequestHandlerException('unauthorized')

        if "namespace" not in data:
            raise RequestHandlerException('invalid namespace')

        if "entity_id" not in data:
            raise RequestHandlerException('invalid entity_id')

        handle = data.get('handle', uuid.uuid4().hex)
        
        if handle in self.subscriptions['state']:
            raise RequestHandlerException('handle already exists')

        self.subscriptions['state'][handle] = {
            "namespace": data['namespace'],
            "entity_id": data['entity_id']
        }

        return handle