static Unit getPreferred(final int numOfDigits) {
      return Arrays.stream(values())
          .filter(u -> numOfDigits <= u.pow + 3)
          .findFirst()
          .orElse(TEther);
    }
Gets preferred.

@param numOfDigits the num of digits
@return the preferred
datatypes/src/main/java/org/hyperledger/besu/datatypes/Wei.java