code: def start_wsgi_server(port, addr='', registry=REGISTRY):
      
      app = make_wsgi_app(registry)
      httpd = make_server(addr, port, app, handler_class=_SilentHandler)
      t = threading.Thread(target=httpd.serve_forever)
      t.daemon = True
      t.start()
docs: Starts a WSGI server for prometheus metrics as a daemon thread.