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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 _yarn_scheduler_metrics(self, rm_address, instance, addl_tags, queue_blacklist):
 """ Get metrics from YARN scheduler """

        metrics_json = self._rest_request_to_json(rm_address, instance, YARN_SCHEDULER_PATH, addl_tags)

        try:
            metrics_json = metrics_json['scheduler']['schedulerInfo']

            if metrics_json['type'] == 'capacityScheduler':
                self._yarn_capacity_scheduler_metrics(metrics_json, addl_tags, queue_blacklist)

        except KeyError:
            pass