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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 _split_message(self, message):
 """Return request_id, data, max_doc_size. :Parameters: - `message`: (request_id, data, max_doc_size) or (request_id, data) """

        if len(message) == 3:
            return message
        else:
            # get_more and kill_cursors messages don't include BSON documents.
            request_id, data = message
            return request_id, data, 0