code: def _resolve_argn(macro, args):
          
          # first, get the number of args
          _id = None
          matches = re.search(r'ARG(?P<id>\d+)', macro)
          if matches is not None:
              _id = int(matches.group('id')) - 1
              try:
                  return args[_id]
              except IndexError:
                  # Required argument not found, returns an empty string
                  return ''
          return ''
docs: Get argument from macro name
          ie : $ARG3$ -> args[2]
  
          :param macro: macro to parse
          :type macro:
          :param args: args given to command line
          :type args:
          :return: argument at position N-1 in args table (where N is the int parsed)
          :rtype: None | str