code: def limit_keyphrases (path, phrase_limit=20):
      
      rank_thresh = None
  
      if isinstance(path, str):
          lex = []
  
          for meta in json_iter(path):
              rl = RankedLexeme(**meta)
              lex.append(rl)
      else:
          lex = path
  
      if len(lex) > 0:
          rank_thresh = statistics.mean([rl.rank for rl in lex])
      else:
              rank_thresh = 0
  
      used = 0
  
      for rl in lex:
          if rl.pos[0] != "v":
              if (used > phrase_limit) or (rl.rank < rank_thresh):
                  return
  
              used += 1
              yield rl.text.replace(" - ", "-")
docs: iterator for the most significant key phrases