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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 labels(self):
 """All labels present in the match patterns. RETURNS (set):
 The string labels. DOCS: https://spacy.io/api/entityruler#labels """

        all_labels = set(self.token_patterns.keys())
        all_labels.update(self.phrase_patterns.keys())
        return tuple(all_labels)