def arguments(args = nil)
      return @_arguments if args.nil?
      @_arguments = []
      [*args].map(&:split).flatten.each do |arg|
        @_arguments << Clin::Argument.new(arg)
      end
    end
def arguments(args = nil)
      return @_arguments if args.nil?
      @_arguments = []
      [*args].map(&:split).flatten.each do |arg|
        @_arguments << Clin::Argument.new(arg)
      end
    end
Set or get the arguments for the command
 @param args [Array<String>] List of arguments to set. If nil it just return the current args.