def run(*argv)
      begin
        docopt_exec argv
      rescue Docopt::Exit => ex
        puts ex.message
        exit 2
      end
    end
def run(*argv)
      begin
        docopt_exec argv
      rescue Docopt::Exit => ex
        puts ex.message
        exit 2
      end
    end
Run the command. This is a wrapper around docopt. It will
 generate the docopt document on the fly, using all the
 information collected so far.