code: def get_score(self, member, default=None, pipe=None):
          
          pipe = self.redis if pipe is None else pipe
          score = pipe.zscore(self.key, self._pickle(member))
  
          if (score is None) and (default is not None):
              score = float(default)
  
          return score
docs: Return the score of *member*, or *default* if it is not in the
          collection.