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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 get_keys(self, bucket, timeout=None):
 """ Lists all keys within a bucket. """

        msg_code = riak.pb.messages.MSG_CODE_LIST_KEYS_REQ
        codec = self._get_codec(msg_code)
        stream = self.stream_keys(bucket, timeout=timeout)
        return codec.decode_get_keys(stream)