code: def scan_items(self):
          
          for k, v in self.redis.hscan_iter(self.key):
              yield self._unpickle_key(k), self._unpickle(v)
docs: Yield each of the ``(key, value)`` pairs from the collection, without
          pulling them all into memory.
  
          .. warning::
              This method is not available on the dictionary collections provided
              by Python.
  
              This method may return the same (key, value) pair multiple times.
              See the `Redis SCAN documentation
              <http://redis.io/commands/scan#scan-guarantees>`_ for details.