@cached_property
    def classifier(self):
        """The classifier."""
        try:
            return self.train()
        except __HOLE__:  # nltk_class has not been defined
            raise ValueError("NLTKClassifier must have a nltk_class"
                            " variable that is not None.")
dataset/ETHPy150Open sloria/TextBlob/textblob/classifiers.py/NLTKClassifier.classifier