def _init_multi_count_metrics(self, pplan_helper):
to_init = [self.metrics[i] for i in self.to_multi_init<EOL>if i in self.metrics and isinstance(self.metrics[i], MultiCountMetric)]<EOL>for out_stream in pplan_helper.get_my_spout().outputs:<EOL><INDENT>stream_id = out_stream.stream.id<EOL>for metric in to_init:<EOL><INDENT>metric.add_key(stream_id)<EOL><DEDENT><DEDENT>
Initializes the default values for a necessary set of MultiCountMetrics