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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 __learn_labels(self, labels):
 """ Learns new labels, this method is intended for internal use Args: labels (:obj:`list` of :obj:`str`):
 Labels to learn """

        if self.feature_length > 0:
            result = list(self.labels.classes_)
        else:
            result = []

        for label in labels:
            result.append(label)
        self.labels.fit(result)