How to use the pyfcm.errors function in pyfcm

def test_init_baseapi():
    try:
        BaseAPI()
        assert False, "Should raise AuthenticationError"
    except errors.AuthenticationError:
        pass

def test_push_service_without_credentials():
    try:
        FCMNotification()
        assert False, "Should raise AuthenticationError without credentials"
    except errors.AuthenticationError:
        pass

def test_notify_topic_subscribers(push_service):
    try:
        push_service.notify_topic_subscribers(
            message_body="Test",
            dry_run=True
        )
        assert False, "Should raise InvalidDataError without topic"
    except errors.InvalidDataError:
        pass

    response = push_service.notify_topic_subscribers(
        topic_name="test",
        message_body="Test",
        message_title="Test",
        dry_run=True
    )

    assert isinstance(response, dict)

elif 'encryption_key' in notification.headers:
                data['enckey'] = notification.headers['encryption_key']

        # registration_ids are the FCM instance tokens (specified during
        # registration.
        router_ttl = min(self.MAX_TTL,
                         max(self.min_ttl, notification.ttl or 0))
        try:
            result = self.fcm.notify_single_device(
                collapse_key=self.collapseKey,
                data_message=data,
                dry_run=self.dryRun or ('dryrun' in router_data),
                registration_id=regid,
                time_to_live=router_ttl,
            )
        except pyfcm.errors.AuthenticationError as e:
            self.log.error("Authentication Error: %s" % e)
            raise RouterException("Server error", status_code=500)
        except ConnectionError as e:
            self.metrics.increment("notification.bridge.error",
                                   tags=make_tags(
                                       self._base_tags,
                                       reason="connection_unavailable"))
            self.log.warn("Could not connect to FCM server: %s" % e)
            raise RouterException("Server error", status_code=502,
                                  log_exception=False)
        except Exception as e:
            self.log.error("Unhandled FCM Error: %s" % e)
            raise RouterException("Server error", status_code=500)
        return self._process_reply(result, notification, router_data,
                                   ttl=router_ttl)