code: func createCompositeKeyForPvtRWSet(txid string, uuid string, blockHeight uint64) []byte {
  	var compositeKey []byte
  	compositeKey = append(compositeKey, prwsetPrefix)
  	compositeKey = append(compositeKey, compositeKeySep)
  	compositeKey = append(compositeKey, createCompositeKeyWithoutPrefixForTxid(txid, uuid, blockHeight)...)
  
  	return compositeKey
  }
docs: // createCompositeKeyForPvtRWSet creates a key for storing private write set
  // in the transient store. The structure of the key is <prwsetPrefix>~txid~uuid~blockHeight.