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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 multiget(self, pairs, **params):
 """Fetches many keys in parallel via threads. :param pairs: list of bucket_type/bucket/key tuple triples :type pairs: list :param params: additional request flags, e.g. r, pr :type params: dict :rtype: list of :class:`RiakObjects <riak.riak_object.RiakObject>`, :class:`Datatypes <riak.datatypes.Datatype>`, or tuples of bucket_type, bucket, key, and the exception raised on fetch """

        if self._multiget_pool:
            params['pool'] = self._multiget_pool
        return riak.client.multi.multiget(self, pairs, **params)