code: def popmin_compat(self, count=1):
          
          pipe = self.database.pipeline()
          r1, r2 = (pipe
                    .zrange(self.key, 0, count - 1, withscores=True)
                    .zremrangebyrank(self.key, 0, count - 1)
                    .execute())
          return r1
docs: Atomically remove the lowest-scoring item(s) in the set. Compatible
          with Redis versions < 5.0.
  
          :returns: a list of item, score tuples or ``None`` if the set is empty.