code: def _get_node_pos(self, key):
          
          if not self._hashring:
              return
  
          k = md5_bytes(key)
          key = (k[3] << 24) | (k[2] << 16) | (k[1] << 8) | k[0]
  
          nodes = self._sorted_keys
          pos = bisect(nodes, key)
  
          if pos == len(nodes):
              return 0
          return pos
docs: Return node position(integer) for a given key or None.