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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 _parse_commit_response(commit_response_pb):
 """Extract response data from a commit response. :type commit_response_pb: :class:`.datastore_pb2.CommitResponse` :param commit_response_pb: The protobuf response from a commit request. :rtype: tuple :returns: The pair of the number of index updates and a list of :class:`.entity_pb2.Key` for each incomplete key that was completed in the commit. """

    mut_results = commit_response_pb.mutation_results
    index_updates = commit_response_pb.index_updates
    completed_keys = [
        mut_result.key for mut_result in mut_results if mut_result.HasField("key")
    ]  # Message field (Key)
    return index_updates, completed_keys