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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 process_read_batch(self, batch):
 """Process a single, partitioned read. :type batch: mapping :param batch: one of the mappings returned from an earlier call to :meth:`generate_read_batches`. :rtype: :class:`~google.cloud.spanner_v1.streamed.StreamedResultSet` :returns: a result set instance which can be used to consume rows. """

        kwargs = copy.deepcopy(batch["read"])
        keyset_dict = kwargs.pop("keyset")
        kwargs["keyset"] = KeySet._from_dict(keyset_dict)
        return self._get_snapshot().read(partition=batch["partition"], **kwargs)