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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 encode_hook(self, hook, msg):
 """ Encodes a commit hook dict into the protobuf message. Used in bucket properties. :param hook: the hook to encode :type hook: dict :param msg: the protobuf message to fill :type msg: riak.pb.riak_pb2.RpbCommitHook :rtype riak.pb.riak_pb2.RpbCommitHook """

        if 'name' in hook:
            msg.name = str_to_bytes(hook['name'])
        else:
            self.encode_modfun(hook, msg.modfun)
        return msg