code: private Observable<PartitionAndSeqno> getSeqnos() {
      return conductor.getSeqnos().flatMap(new Func1<ByteBuf, Observable<PartitionAndSeqno>>() {
        @Override
        public Observable<PartitionAndSeqno> call(ByteBuf buf) {
          int numPairs = buf.readableBytes() / 10; // 2 byte short + 8 byte long
          List<PartitionAndSeqno> pairs = new ArrayList<>(numPairs);
          for (int i = 0; i < numPairs; i++) {
            pairs.add(new PartitionAndSeqno(buf.getShort(10 * i), buf.getLong(10 * i + 2)));
          }
          buf.release();
          return Observable.from(pairs);
        }
      });
    }
docs: Get the current sequence numbers from all partitions.
  
  @return an {@link Observable} of partition and sequence number.