How to use the universal-user-agent.getUserAgent function in universal-user-agent

constructor(options = {}) {
    const hook = new beforeAfterHook.Collection();
    const requestDefaults = {
      baseUrl: request.request.endpoint.DEFAULTS.baseUrl,
      headers: {},
      request: Object.assign({}, options.request, {
        hook: hook.bind(null, "request")
      }),
      mediaType: {
        previews: [],
        format: ""
      }
    }; // prepend default user agent with `options.userAgent` if set

    requestDefaults.headers["user-agent"] = [options.userAgent, `octokit-core.js/${VERSION} ${universalUserAgent.getUserAgent()}`].filter(Boolean).join(" ");

    if (options.baseUrl) {
      requestDefaults.baseUrl = options.baseUrl;
    }

    if (options.previews) {
      requestDefaults.mediaType.previews = options.previews;
    }

    if (options.timeZone) {
      requestDefaults.headers["time-zone"] = options.timeZone;
    }

    this.request = request.request.defaults(requestDefaults);
    this.graphql = graphql.withCustomRequest(this.request).defaults(_objectSpread2(_objectSpread2({}, requestDefaults), {}, {
      baseUrl: requestDefaults.baseUrl.replace(/\/api\/v3$/, "/api")

const hook = new Collection();
        const requestDefaults = {
            baseUrl: request.endpoint.DEFAULTS.baseUrl,
            headers: {},
            request: Object.assign({}, options.request, {
                hook: hook.bind(null, "request"),
            }),
            mediaType: {
                previews: [],
                format: "",
            },
        };
        // prepend default user agent with `options.userAgent` if set
        requestDefaults.headers["user-agent"] = [
            options.userAgent,
            `octokit-core.js/${VERSION} ${getUserAgent()}`,
        ]
            .filter(Boolean)
            .join(" ");
        if (options.baseUrl) {
            requestDefaults.baseUrl = options.baseUrl;
        }
        if (options.previews) {
            requestDefaults.mediaType.previews = options.previews;
        }
        if (options.timeZone) {
            requestDefaults.headers["time-zone"] = options.timeZone;
        }
        this.request = request.defaults(requestDefaults);
        this.graphql = withCustomRequest(this.request).defaults({
            ...requestDefaults,
            baseUrl: requestDefaults.baseUrl.replace(/\/api\/v3$/, "/api"),

const hook = new Collection();
        const requestDefaults = {
            baseUrl: request.endpoint.DEFAULTS.baseUrl,
            headers: {},
            request: Object.assign({}, options.request, {
                hook: hook.bind(null, "request"),
            }),
            mediaType: {
                previews: [],
                format: "",
            },
        };
        // prepend default user agent with `options.userAgent` if set
        requestDefaults.headers["user-agent"] = [
            options.userAgent,
            `octokit-core.js/${VERSION} ${getUserAgent()}`,
        ]
            .filter(Boolean)
            .join(" ");
        if (options.baseUrl) {
            requestDefaults.baseUrl = options.baseUrl;
        }
        if (options.previews) {
            requestDefaults.mediaType.previews = options.previews;
        }
        if (options.timeZone) {
            requestDefaults.headers["time-zone"] = options.timeZone;
        }
        this.request = request.defaults(requestDefaults);
        this.graphql = withCustomRequest(this.request).defaults({
            ...requestDefaults,
            baseUrl: requestDefaults.baseUrl.replace(/\/api\/v3$/, "/api"),

)
    );
    clientDefaults.request.agent = options.agent;
  }

  if (options.headers) {
    deprecateOptionsHeaders(
      log,
      new Deprecation(
        "[@octokit/rest] new Octokit({headers}) is deprecated. Use {userAgent, previews} instead. See https://github.com/octokit/request.js#request"
      )
    );
  }

  const userAgentOption = clientDefaults.headers["user-agent"];
  const defaultUserAgent = `octokit.js/${pkg.version} ${getUserAgent()}`;

  clientDefaults.headers["user-agent"] = [userAgentOption, defaultUserAgent]
    .filter(Boolean)
    .join(" ");

  clientDefaults.request.hook = hook.bind(null, "request");

  return clientDefaults;
}