code: func (mvcc *MVCCLevelDB) RawBatchPut(keys, values [][]byte) {
  	mvcc.mu.Lock()
  	defer mvcc.mu.Unlock()
  
  	batch := &leveldb.Batch{}
  	for i, key := range keys {
  		value := values[i]
  		if value == nil {
  			value = []byte{}
  		}
  		batch.Put(key, value)
  	}
  	terror.Log(mvcc.db.Write(batch, nil))
  }
docs: // RawBatchPut implements the RawKV interface