def lemmas(self):
        """Returns a list of the lemmatized text of each token.
        Returns None if this annotation was not included.
        """
        if 'lemma' not in self.annotators:
            return None
        return [t[self.LEMMA] for t in self.data]
Returns a list of the lemmatized text of each token.
        Returns None if this annotation was not included.
        
simlm/misc/dpr/evaluate_dpr_retrieval.py