Set<ReplicaId> getPeerLeaderReplicaSet(String leaderPartitionName) {
      ReplicaId localReplica = storeManager.getReplica(leaderPartitionName);
      PartitionId leaderPartition = localReplica.getPartitionId();
      Set<ReplicaId> peerLeaderReplicaSet =
          new HashSet<>(leaderPartition.getReplicaIdsByState(ReplicaState.LEADER, null));
      peerLeaderReplicaSet.remove(localReplica);
      return peerLeaderReplicaSet;
    }
Retrieves the set of peer leader replicas (in remote data centers) for the given leader partition on this node
@param leaderPartitionName leader partition name
@return set of peer leader replicas
ambry-replication/src/main/java/com/github/ambry/replication/ReplicationEngine.java