code: func (txPvtRwSet *TxPvtRwSet) ToProtoBytes() ([]byte, error) {
  	var protoMsg *rwset.TxPvtReadWriteSet
  	var err error
  	if protoMsg, err = txPvtRwSet.toProtoMsg(); err != nil {
  		return nil, err
  	}
  	return proto.Marshal(protoMsg)
  }
docs: // ToProtoBytes constructs 'TxPvtReadWriteSet' proto message and serializes using protobuf Marshal