How to use the @nteract/messaging.shutdownRequest function in @nteract/messaging

// Validate the input, do nothing if invalid kernel info is provided.
  if (!(kernel && (kernel.channels || kernel.spawn))) {
    return Promise.resolve(true);
  }

  // Fallback to forcefully shutting the kernel down.
  function handleShutdownFailure(err) {
    console.error(
      `Could not gracefully shutdown the kernel because of the
      following error.  nteract will now forcefully shutdown the kernel.`,
      err
    );
    forceShutdownKernel(kernel);
  }

  const request = shutdownRequest({ restart: false });

  const shutDownReply = kernel.channels
    .pipe(
      childOf(request),
      ofMessageType("shutdown_reply"),
      map(msg => msg.content)
    )
    .toPromise();

  kernel.channels.next(request);
  // Attempt to gracefully terminate the kernel.

  return shutDownReply
    .then(k => {
      // At this point, the kernel has cleaned up its resources.  Now we can
      // terminate the process and cleanup handles by calling forceShutdownKernel

}

      const kernel = selectors.kernel(state$.value, { kernelRef });

      if (!kernel) {
        // tslint:disable-next-line:no-console
        console.warn("tried to kill a kernel that doesn't exist");
        return empty();
      }

      // Ignore the action if the specified kernel is not ZMQ.
      if (kernel.type !== "zeromq") {
        return empty();
      }

      const request = shutdownRequest({ restart: false });

      // Try to make a shutdown request
      // If we don't get a response within X time, force a shutdown
      // Either way do the same cleanup
      const shutDownHandling = kernel.channels.pipe(
        childOf(request),
        ofMessageType("shutdown_reply"),
        first(),
        // If we got a reply, great! :)
        map((msg: { content: { restart: boolean } }) =>
          actions.shutdownReplySucceeded({ content: msg.content, kernelRef })
        ),
        // If we don't get a response within 2s, assume failure :(
        timeout(1000 * 2),
        catchError(err =>
          of(actions.shutdownReplyTimedOut({ error: err, kernelRef }))

}

      const kernel = selectors.kernel(state$.value, { kernelRef });

      if (!kernel) {
        // tslint:disable-next-line:no-console
        console.warn("tried to kill a kernel that doesn't exist");
        return empty();
      }

      // Ignore the action if the specified kernel is not ZMQ.
      if (kernel.type !== "zeromq") {
        return empty();
      }

      const request = shutdownRequest({ restart: false });

      // Try to make a shutdown request
      // If we don't get a response within X time, force a shutdown
      // Either way do the same cleanup
      const shutDownHandling = kernel.channels.pipe(
        childOf(request),
        ofMessageType("shutdown_reply"),
        first(),
        // If we got a reply, great! :)
        map((msg: { content: { restart: boolean } }) =>
          actions.shutdownReplySucceeded({ content: msg.content, kernelRef })
        ),
        // If we don't get a response within 2s, assume failure :(
        timeout(1000 * 2),
        catchError(err =>
          of(actions.shutdownReplyTimedOut({ error: err, kernelRef }))

shutdownEpic(timeoutMs: number = 2000) {
    const request: JupyterMessage<"shutdown_request", any> = shutdownRequest({
      restart: false
    });

    // Try to make a shutdown request
    // If we don't get a response within X time, force a shutdown
    // Either way do the same cleanup
    const shutDownHandling = this.channels.pipe(
      /* Get the first response to our message request. */
      childOf(request),
      ofMessageType("shutdown_reply"),
      first(),
      // If we got a reply, great! :)
      map((msg: { content: { restart: boolean } }) => {
        return {
          status: "shutting down",
          content: msg.content