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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 _update_count(self, index):
 """Updates num_update. Parameters index : int or list of int The index to be updated. """

        if not isinstance(index, (list, tuple)):
            index = [index]
        for idx in index:
            if idx not in self._index_update_count:
                self._index_update_count[idx] = self.begin_num_update
            self._index_update_count[idx] += 1
            self.num_update = max(self._index_update_count[idx], self.num_update)