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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 collect(self):
 # pragma: NO COVER """Collect fetches the statistics from OpenCensus and delivers them as Prometheus Metrics. Collect is invoked every time a prometheus.Gatherer is run for example when the HTTP endpoint is invoked by Prometheus. """

        for v_name, view_data in self.view_name_to_data_map.items():
            if v_name not in self.registered_views:
                continue
            desc = self.registered_views[v_name]
            for tag_values in view_data.tag_value_aggregation_data_map:
                agg_data = view_data.tag_value_aggregation_data_map[tag_values]
                metric = self.to_metric(desc, tag_values, agg_data)
                yield metric