working_formatter.scala

val formattedPredictions: List[Option[String]] = predictions.map(_.classPredictions.headOption.map(_.prediction))
val formattedLabels: List[Option[String]] = data.map(_.label)
val (guesses, truths): (List[String], List[String]) = (
  for {
  (guess, truth) <- formattedPredictions zip formattedLabels
  realGuess <- guess
  realTruth <- truth
}yield(realGuess, realTruth)
  ).unzip