code: def score(self, y_true, y_pred):
          
          score = f1_score(y_true, y_pred)
          print(' - f1: {:04.2f}'.format(score * 100))
          print(classification_report(y_true, y_pred, digits=4))
          return score
docs: Calculate f1 score.
  
          Args:
              y_true (list): true sequences.
              y_pred (list): predicted sequences.
  
          Returns:
              score: f1 score.