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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 start_http_server(self, port, host='0.0.0.0', endpoint=None):
 """ Start an HTTP server for exposing the metrics, if the `should_start_http_server` function says we should, otherwise just return. Uses the implementation from `prometheus_client` rather than a Flask app. :param port: the HTTP port to expose the metrics endpoint on :param host: the HTTP host to listen on (default: `0.0.0.0`) :param endpoint: **ignored**, the HTTP server will respond on any path """


        if self.should_start_http_server():
            pc_start_http_server(port, host, registry=self.registry)