@Value.Derived
  public Optional<Bytes> getPayload() {
    return getInput().or(this::getData);
  }
Returns either the 'input' or 'data' field, depending on which is present, or empty if neither
is present.

@return the payload, or empty if none is present.
ethereum/core/src/main/java/org/hyperledger/besu/ethereum/transaction/CallParameter.java