code: func RunServices(dockerCli command.Cli, opts options.Services) error {
  	ctx := context.Background()
  	client := dockerCli.Client()
  
  	filter := getStackFilterFromOpt(opts.Namespace, opts.Filter)
  	services, err := client.ServiceList(ctx, types.ServiceListOptions{Filters: filter})
  	if err != nil {
  		return err
  	}
  
  	// if no services in this stack, print message and exit 0
  	if len(services) == 0 {
  		fmt.Fprintf(dockerCli.Err(), "Nothing found in stack: %s\n", opts.Namespace)
  		return nil
  	}
  
  	info := map[string]service.ListInfo{}
  	if !opts.Quiet {
  		taskFilter := filters.NewArgs()
  		for _, service := range services {
  			taskFilter.Add("service", service.ID)
  		}
  
  		tasks, err := client.TaskList(ctx, types.TaskListOptions{Filters: taskFilter})
  		if err != nil {
  			return err
  		}
  
  		nodes, err := client.NodeList(ctx, types.NodeListOptions{})
  		if err != nil {
  			return err
  		}
  
  		info = service.GetServicesStatus(services, nodes, tasks)
  	}
  
  	format := opts.Format
  	if len(format) == 0 {
  		if len(dockerCli.ConfigFile().ServicesFormat) > 0 && !opts.Quiet {
  			format = dockerCli.ConfigFile().ServicesFormat
  		} else {
  			format = formatter.TableFormatKey
  		}
  	}
  
  	servicesCtx := formatter.Context{
  		Output: dockerCli.Out(),
  		Format: service.NewListFormat(format, opts.Quiet),
  	}
  	return service.ListFormatWrite(servicesCtx, services, info)
  }
docs: // RunServices is the swarm implementation of docker stack services