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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 setup_prometheus(self, registry=None):
 """Setup Prometheus."""

        kwargs = {}
        if registry:
            kwargs["registry"] = registry
        self.metrics = PrometheusMetrics(self.app, **kwargs)
        try:
            version = pkg_resources.require(self.app.name)[0].version
        except pkg_resources.DistributionNotFound:
            version = "unknown"
        self.metrics.info(
            "app_info", "Application info", version=version, appname=self.app.name
        )
        self.app.logger.info("Prometheus is enabled.")