code: func (l *kvLedger) GetBlockByTxID(txID string) (*common.Block, error) {
  	block, err := l.blockStore.RetrieveBlockByTxID(txID)
  	l.blockAPIsRWLock.RLock()
  	l.blockAPIsRWLock.RUnlock()
  	return block, err
  }
docs: // GetBlockByTxID returns a block which contains a transaction