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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 clear_data(self):
 """Clear both ontology and annotation data. Parameters Returns ------- None """

        self.clear_annotation_data()
        self.terms = {}
        self._alt_id = {}
        self._syn2id = {}
        self._name2id = {}
        self._flattened = False