code: func (db *nodeDB) deleteNode(id NodeID) error {
  	deleter := db.lvl.NewIterator(util.BytesPrefix(makeKey(id, "")), nil)
  	for deleter.Next() {
  		if err := db.lvl.Delete(deleter.Key(), nil); err != nil {
  			return err
  		}
  	}
  	return nil
  }
docs: // deleteNode deletes all information/keys associated with a node.