How to use the @jupyterlab/completer.KernelConnector function in @jupyterlab/completer

void session.kernel.ready.then(() => {
        const lang = session.kernel!.info!.language_info;
        const mimeType = mimeService.getMimeTypeByLanguage(lang);
        cellWidget.model.mimeType = mimeType;
      });
    }
  });

  // Use the default kernel.
  session.kernelPreference = { autoStartDefault: true };

  // Set up a completer.
  const editor = cellWidget.editor;
  const model = new CompleterModel();
  const completer = new Completer({ editor, model });
  const connector = new KernelConnector({ session });
  const handler = new CompletionHandler({ completer, connector });

  // Set the handler's editor.
  handler.editor = editor;

  // Hide the widget when it first loads.
  completer.hide();

  // Create a toolbar for the cell.
  const toolbar = new Toolbar();
  toolbar.addItem('spacer', Toolbar.createSpacerItem());
  toolbar.addItem('interrupt', Toolbar.createInterruptButton(session));
  toolbar.addItem('restart', Toolbar.createRestartButton(session));
  toolbar.addItem('name', Toolbar.createKernelNameItem(session));
  toolbar.addItem('status', Toolbar.createKernelStatusItem(session));

rendermime,
    contentFactory,
    mimeTypeService: editorServices.mimeTypeService
  });
  docRegistry.addModelFactory(mFactory);
  docRegistry.addWidgetFactory(wFactory);

  let notebookPath = PageConfig.getOption('notebookPath');
  let nbWidget = docManager.open(notebookPath) as NotebookPanel;
  let palette = new CommandPalette({ commands });

  const editor =
    nbWidget.content.activeCell && nbWidget.content.activeCell.editor;
  const model = new CompleterModel();
  const completer = new Completer({ editor, model });
  const connector = new KernelConnector({ session: nbWidget.session });
  const handler = new CompletionHandler({ completer, connector });

  // Set the handler's editor.
  handler.editor = editor;

  // Listen for active cell changes.
  nbWidget.content.activeCellChanged.connect((sender, cell) => {
    handler.editor = cell && cell.editor;
  });

  // Hide the widget when it first loads.
  completer.hide();

  let panel = new SplitPanel();
  panel.id = 'main';
  panel.orientation = 'horizontal';

});
  docRegistry.addModelFactory(mFactory);
  docRegistry.addWidgetFactory(wFactory);

  let notebookPath = PageConfig.getOption('notebookPath');
  let nbWidget = docManager.open(notebookPath) as NotebookPanel;

  // Create menu bar.
  let menuBar = new MenuBar();
  menuBar.addClass('notebookMenuBar');

  const editor =
    nbWidget.content.activeCell && nbWidget.content.activeCell.editor;
  const model = new CompleterModel();
  const completer = new Completer({ editor, model });
  const connector = new KernelConnector({ session: nbWidget.session });
  const handler = new CompletionHandler({ completer, connector });

  // Set the handler's editor.
  handler.editor = editor;

  // Listen for active cell changes.
  nbWidget.content.activeCellChanged.connect((sender, cell) => {
    handler.editor = cell && cell.editor;
  });

  // Hide the widget when it first loads.
  completer.hide();

  // Create panel with menu bar above the notebook widget
  let panel = new SplitPanel();
  panel.id = 'main';

rendermime,
    contentFactory,
    mimeTypeService: editorServices.mimeTypeService
  });
  docRegistry.addModelFactory(mFactory);
  docRegistry.addWidgetFactory(wFactory);

  let notebookPath = PageConfig.getOption('notebookPath');
  let nbWidget = docManager.open(notebookPath) as NotebookPanel;
  let palette = new CommandPalette({ commands });

  const editor =
    nbWidget.content.activeCell && nbWidget.content.activeCell.editor;
  const model = new CompleterModel();
  const completer = new Completer({ editor, model });
  const connector = new KernelConnector({ session: nbWidget.session });
  const handler = new CompletionHandler({ completer, connector });

  // Set the handler's editor.
  handler.editor = editor;

  // Listen for active cell changes.
  nbWidget.content.activeCellChanged.connect((sender, cell) => {
    handler.editor = cell && cell.editor;
  });

  // Hide the widget when it first loads.
  completer.hide();

  let panel = new SplitPanel();
  panel.id = 'main';
  panel.orientation = 'horizontal';

session.kernel.ready.then(() => {
      const lang = session.kernel.info.language_info;
      const mimeType = mimeService.getMimeTypeByLanguage(lang);
      cellWidget.model.mimeType = mimeType;
    });
  });

  // Start the default kernel.
  session.kernelPreference = { autoStartDefault: true };
  session.initialize();

  // Set up a completer.
  const editor = cellWidget.editor;
  const model = new CompleterModel();
  const completer = new Completer({ editor, model });
  const connector = new KernelConnector({ session });
  const handler = new CompletionHandler({ completer, connector });

  // Set the handler's editor.
  handler.editor = editor;

  // Hide the widget when it first loads.
  completer.hide();

  // Create a toolbar for the cell.
  const toolbar = new Toolbar();
  toolbar.addItem('spacer', Toolbar.createSpacerItem());
  toolbar.addItem('interrupt', Toolbar.createInterruptButton(session));
  toolbar.addItem('restart', Toolbar.createRestartButton(session));
  toolbar.addItem('name', Toolbar.createKernelNameItem(session));
  toolbar.addItem('status', Toolbar.createKernelStatusItem(session));

constructor(props: CompleterProps) {
    super(props);

    const editor =
      this.props.notebookPanel.content.activeCell &&
      this.props.notebookPanel.content.activeCell.editor;
    const model = new CompleterModel();
    this.completer = new Completer({ editor, model });
    const connector = new KernelConnector({
      session: this.props.notebookPanel.session
    });
    this.handler = new CompletionHandler({
      completer: this.completer,
      connector
    });
    // Set the handler's editor.
    this.handler.editor = editor;

    // Listen for active cell changes.
    this.props.notebookPanel.content.activeCellChanged.connect(
      (sender, cell) => {
        this.handler.editor = cell && cell.editor;
      }
    );

beforeAll(async () => {
    session = await createClientSession();
    await (session as ClientSession).initialize();
    connector = new KernelConnector({ session });
  });

constructor(options: LSPConnector.IOptions) {
    super();
    this._editor = options.editor;
    this._connections = options.connections;
    this.virtual_editor = options.virtual_editor;
    this._context_connector = new ContextConnector({ editor: options.editor });
    if (options.session) {
      let kernel_options = { editor: options.editor, session: options.session };
      this._kernel_connector = new KernelConnector(kernel_options);
      this._kernel_and_context_connector = new CompletionConnector(
        kernel_options
      );
    }
    this.options = options;
  }