code: func (db *BytesConnectionEtcd) NewBroker(prefix string) keyval.BytesBroker {
  	return &BytesBrokerWatcherEtcd{
  		Logger:    db.Logger,
  		kv:        namespace.NewKV(db.etcdClient, prefix),
  		lessor:    db.lessor,
  		opTimeout: db.opTimeout,
  		watcher:   namespace.NewWatcher(db.etcdClient, prefix),
  	}
  }
docs: // NewBroker creates a new instance of a proxy that provides
  // access to etcd. The proxy will reuse the connection from BytesConnectionEtcd.
  // <prefix> will be prepended to the key argument in all calls from the created
  // BytesBrokerWatcherEtcd. To avoid using a prefix, pass keyval. Root constant as
  // an argument.