:in

def param(self, *args, **kwargs):
    " :in   "
    for first, second in pairwise(args):
      if isinstance(second, list):
        if not isinstance(second[0], list):
          " add a logical _or_ " 
          self._input.append((
            u"[{0} ...]".format(first), second)) 
        else:
          " relations, list of list"
          self._input.append((
            u"[[{0}]]".format(first), second)) 
      elif isinstance(second, tuple):
        " tuple "
        self._input.append((
          u"[{0}]".format(first), list(second))) 
      else:
        " nothing special "
        self._input.append((first,second)) 
    return self