How to use the @jupyterlab/filebrowser.FileUploadStatus function in @jupyterlab/filebrowser

activate: (
    app: JupyterFrontEnd,
    statusBar: IStatusBar,
    browser: IFileBrowserFactory
  ) => {
    const item = new FileUploadStatus({
      tracker: browser.tracker
    });

    statusBar.registerStatusItem(
      '@jupyterlab/filebrowser-extension:file-upload-status',
      {
        item,
        align: 'middle',
        isActive: () => {
          return !!item.model && item.model.items.length > 0;
        },
        activeStateChanged: item.model.stateChanged
      }
    );
  }
};

activate: (
    app: JupyterFrontEnd,
    statusBar: IStatusBar,
    browser: IFileBrowserFactory
  ) => {
    const item = new FileUploadStatus({
      tracker: browser.tracker
    });

    statusBar.registerStatusItem(
      '@jupyterlab/filebrowser-extension:file-upload-status',
      {
        item,
        align: 'middle',
        isActive: () => {
          return !!item.model && item.model.items.length > 0;
        },
        activeStateChanged: item.model.stateChanged
      }
    );
  }
};