parameters: (self, word_ids)
return_statement: return [self.id2word[w_id] for w_id in word_ids]
docstring: Convert list of indices into words.
          @param word_ids (list[int]): list of word ids
          @return sents (list[str]): list of words
docstring_summary: Convert list of indices into words.
docstring_tokens: Convert list of indices into words .
function: def indices2words(self, word_ids):
          """ Convert list of indices into words.
          @param word_ids (list[int]): list of word ids
          @return sents (list[str]): list of words
          """
          return [self.id2word[w_id] for w_id in word_ids]
function_tokens: def indices2words ( self , word_ids ) : return [ self . id2word [ w_id ] for w_id in word_ids ]