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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 _select_broker_pair(self, rg_destination, victim_partition):
 """Select best-fit source and destination brokers based on partition count and presence of partition over the broker. * Get overloaded and underloaded brokers Best-fit Selection Criteria: Source broker: Select broker containing the victim-partition with maximum partitions. Destination broker: NOT containing the victim-partition with minimum partitions. If no such broker found, return first broker. This helps in ensuring:- * Topic-partitions are distributed across brokers. * Partition-count is balanced across replication-groups. """

        broker_source = self._elect_source_broker(victim_partition)
        broker_destination = rg_destination._elect_dest_broker(victim_partition)
        return broker_source, broker_destination