How to use the node-opcua-service-subscription.DeleteSubscriptionsResponse function in node-opcua-service-subscription

g_session.deleteSubscriptions(request, function (err, response) {
            if (!err) {
                response.should.be.instanceOf(subscription_service.DeleteSubscriptionsResponse);
            }
            done(err);
        });
    });

ClientSession.prototype.deleteSubscriptions = function (options, callback) {
    this._defaultRequest(
        subscription_service.DeleteSubscriptionsRequest,
        subscription_service.DeleteSubscriptionsResponse,
        options, callback);
};

const CloseSessionResponse = session_service.CloseSessionResponse;

const DeleteMonitoredItemsRequest = subscription_service.DeleteMonitoredItemsRequest;
const DeleteMonitoredItemsResponse = subscription_service.DeleteMonitoredItemsResponse;

const RepublishRequest = subscription_service.RepublishRequest;
const RepublishResponse = subscription_service.RepublishResponse;

const PublishRequest = subscription_service.PublishRequest;
const PublishResponse = subscription_service.PublishResponse;

const CreateSubscriptionRequest = subscription_service.CreateSubscriptionRequest;
const CreateSubscriptionResponse = subscription_service.CreateSubscriptionResponse;

const DeleteSubscriptionsRequest = subscription_service.DeleteSubscriptionsRequest;
const DeleteSubscriptionsResponse = subscription_service.DeleteSubscriptionsResponse;

const TransferSubscriptionsRequest = subscription_service.TransferSubscriptionsRequest;
const TransferSubscriptionsResponse = subscription_service.TransferSubscriptionsResponse;

const CreateMonitoredItemsRequest = subscription_service.CreateMonitoredItemsRequest;
const CreateMonitoredItemsResponse = subscription_service.CreateMonitoredItemsResponse;

const ModifyMonitoredItemsRequest = subscription_service.ModifyMonitoredItemsRequest;
const ModifyMonitoredItemsResponse = subscription_service.ModifyMonitoredItemsResponse;
const MonitoredItemModifyResult = subscription_service.MonitoredItemModifyResult;

const MonitoredItemCreateResult = subscription_service.MonitoredItemCreateResult;
const SetPublishingModeRequest = subscription_service.SetPublishingModeRequest;
const SetPublishingModeResponse = subscription_service.SetPublishingModeResponse;

const CallRequest = call_service.CallRequest;