code: func PsCommand(factory app.ProjectFactory) cli.Command {
  	return cli.Command{
  		Name:   "ps",
  		Usage:  "List containers",
  		Action: app.WithProject(factory, app.ProjectPs),
  		Flags: []cli.Flag{
  			cli.BoolFlag{
  				Name:  "q",
  				Usage: "Only display IDs",
  			},
  		},
  	}
  }
docs: // PsCommand defines the libcompose ps subcommand.