public Optional<BigInteger> getYParity() {
    return Optional.ofNullable(transactionWithMetadata.getTransaction().getYParity());
  }
Retrieves the Y parity of the transaction's signature.

@return an Optional containing a BigInteger object representing the Y parity of the
    transaction's signature.
ethereum/api/src/main/java/org/hyperledger/besu/ethereum/api/graphql/internal/pojoadapter/TransactionAdapter.java