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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def score(self, y_true, y_pred):
 """Calculate f1 score. Args: y_true (list):
 true sequences. y_pred (list):
 predicted sequences. Returns: score: f1 score. """

        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