How to use the @microsoft/api-extractor-model.ApiItemKind.Namespace function in @microsoft/api-extractor-model

private _buildTocItems2(apiItems: ReadonlyArray): IYamlTocItem[] {
    const tocItems: IYamlTocItem[] = [];
    for (const apiItem of apiItems) {
      let tocItem: IYamlTocItem;

      if (apiItem.kind === ApiItemKind.Namespace) {
        // Namespaces don't have nodes yet
        tocItem = {
          name: apiItem.displayName
        };
      } else {
        if (this._shouldEmbed(apiItem.kind)) {
          // Don't generate table of contents items for embedded definitions
          continue;
        }

        if (apiItem.kind === ApiItemKind.Package) {
          tocItem = {
            name: PackageName.getUnscopedName(apiItem.displayName),
            uid: this._getUid(apiItem)
          };
        } else {

private _buildTocItems(apiItems: ReadonlyArray): IYamlTocItem[] {
    const tocItems: IYamlTocItem[] = [];
    for (const apiItem of apiItems) {
      let tocItem: IYamlTocItem;

      if (apiItem.kind === ApiItemKind.Namespace) {
        // Namespaces don't have nodes yet
        tocItem = {
          name: apiItem.displayName
        };
      } else {
        if (this._shouldEmbed(apiItem.kind)) {
          // Don't generate table of contents items for embedded definitions
          continue;
        }

        if (apiItem.kind === ApiItemKind.Package) {
          tocItem = {
            name: PackageName.getUnscopedName(apiItem.displayName),
            uid: this._getUid(apiItem)
          };
        } else {

output.appendNode(new DocHeading({ configuration, title: `${scopedName} class` }));
        break;
      case ApiItemKind.Enum:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} enum` }));
        break;
      case ApiItemKind.Interface:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} interface` }));
        break;
      case ApiItemKind.Method:
      case ApiItemKind.MethodSignature:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} method` }));
        break;
      case ApiItemKind.Function:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} function` }));
        break;
      case ApiItemKind.Namespace:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} namespace` }));
        break;
      case ApiItemKind.Package:
        const unscopedPackageName: string = PackageName.getUnscopedName(apiItem.displayName);
        console.log(apiItem.displayName);
        output.appendNode(new DocHeading({ configuration, title: `${unscopedPackageName} package` }));
        break;
      case ApiItemKind.Property:
      case ApiItemKind.PropertySignature:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} property` }));
        break;
      case ApiItemKind.TypeAlias:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} type` }));
        break;
      case ApiItemKind.Variable:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} variable` }));

break;
      case ApiItemKind.Constructor:
      case ApiItemKind.ConstructSignature:
        output.appendNode(new DocHeading({ configuration, title: scopedName }));
        break;
      case ApiItemKind.Method:
      case ApiItemKind.MethodSignature:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} method` }));
        break;
      case ApiItemKind.Function:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} function` }));
        break;
      case ApiItemKind.Model:
        output.appendNode(new DocHeading({ configuration, title: `API Reference` }));
        break;
      case ApiItemKind.Namespace:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} namespace` }));
        break;
      case ApiItemKind.Package:
        console.log(`Writing ${apiItem.displayName} package`);
        const unscopedPackageName: string = PackageName.getUnscopedName(apiItem.displayName);
        output.appendNode(new DocHeading({ configuration, title: `${unscopedPackageName} package` }));
        break;
      case ApiItemKind.Property:
      case ApiItemKind.PropertySignature:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} property` }));
        break;
      case ApiItemKind.TypeAlias:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} type` }));
        break;
      case ApiItemKind.Variable:
        output.appendNode(new DocHeading({ configuration, title: `${scopedName} variable` }));

private _flattenNamespaces(items: ReadonlyArray): ApiItem[] {
    const flattened: ApiItem[] = [];
    for (const item of items) {
      if (item.kind === ApiItemKind.Namespace) {
        flattened.push(...this._flattenNamespaces(item.members));
      } else {
        flattened.push(item);
      }
    }
    return flattened;
  }