How to use the whatwg-url.serializeHost function in whatwg-url

get hostname() {
    reinitializeURL(this);
    const { url } = this;

    if (url === null || url.host === null) {
      return "";
    }

    return whatwgURL.serializeHost(url.host);
  }

get hostname() {
    reinitializeURL(this);
    const { url } = this;

    if (url === null || url.host === null) {
      return "";
    }

    return whatwgURL.serializeHost(url.host);
  }

get hostname() {
    reinitializeURL(this);
    const { url } = this;

    if (url === null || url.host === null) {
      return "";
    }

    return whatwgURL.serializeHost(url.host);
  }

get host() {
    reinitializeURL(this);
    const { url } = this;

    if (url === null || url.host === null) {
      return "";
    }

    if (url.port === null) {
      return whatwgURL.serializeHost(url.host);
    }

    return whatwgURL.serializeHost(url.host) + ":" + whatwgURL.serializeInteger(url.port);
  }

get host() {
    reinitializeURL(this);
    const { url } = this;

    if (url === null || url.host === null) {
      return "";
    }

    if (url.port === null) {
      return whatwgURL.serializeHost(url.host);
    }

    return whatwgURL.serializeHost(url.host) + ":" + whatwgURL.serializeInteger(url.port);
  }

get hostname() {
    if (this._url.host === null) {
      return "";
    }

    return whatwgURL.serializeHost(this._url.host);
  }
  set hostname(v) {

get host() {
    const url = this._url;

    if (url.host === null) {
      return "";
    }
    if (url.port === null) {
      return whatwgURL.serializeHost(url.host);
    }

    return whatwgURL.serializeHost(url.host) + ":" + whatwgURL.serializeInteger(url.port);
  }
  set host(v) {