keras/src/layers/preprocessing/index_lookup.py/IndexLookup/reset_state
class IndexLookup:    def reset_state(self):
        if self._has_input_vocabulary:
            return

        self.token_counts.remove(self.token_counts.export()[0])
        if self.output_mode == "tf_idf":
            self.token_document_counts.remove(
                self.token_document_counts.export()[0]
            )
            self.num_documents.assign(0)