code: public static alluxio.grpc.TieredIdentity toProto(TieredIdentity tieredIdentity) {
      return alluxio.grpc.TieredIdentity.newBuilder()
          .addAllTiers(
              tieredIdentity.getTiers().stream().map(GrpcUtils::toProto).collect(Collectors.toList()))
          .build();
    }
docs: Converts wire type to proto type.
  
  @param tieredIdentity the wire representation to convert
  @return the converted proto representation