code: def _morphy_best(word, pos=None):
      
      results = []
      if pos is None:
          pos = 'nvar'
      for pos_item in pos:
          results.extend(morphy(word, pos_item))
      if not results:
          return None
      results.sort(key=lambda x: _word_badness(x))
      return results[0]
docs: Get the most likely stem for a word using Morphy, once the input has been
      pre-processed by morphy_stem().