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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 _register_lemme(self, lemma):
 """ Register a lemma into the Lemmatiseur :param lemma: Lemma to register :return: """

        if lemma.cle() not in self.lemmatiseur._lemmes:
            self.ajRadicaux(lemma)
            self.lemmatiseur._lemmes[lemma.cle()] = lemma