# File lib/thor.rb, line 498
  def help(command = nil, subcommand = false)
    if command
      if self.class.subcommands.include? command
        self.class.subcommand_classes[command].help(shell, true)
      else
        self.class.command_help(shell, command)
      end
    else
      self.class.help(shell, subcommand)
    end
  end