code: func NewDiffCommand(dockerCli command.Cli) *cobra.Command {
  	var opts diffOptions
  
  	return &cobra.Command{
  		Use:   "diff CONTAINER",
  		Short: "Inspect changes to files or directories on a container's filesystem",
  		Args:  cli.ExactArgs(1),
  		RunE: func(cmd *cobra.Command, args []string) error {
  			opts.container = args[0]
  			return runDiff(dockerCli, &opts)
  		},
  	}
  }
docs: // NewDiffCommand creates a new cobra.Command for `docker diff`