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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(port, addr='', registry=REGISTRY):
 """Starts an HTTP server for prometheus metrics as a daemon thread"""

    CustomMetricsHandler = MetricsHandler.factory(registry)
    httpd = _ThreadingSimpleServer((addr, port), CustomMetricsHandler)
    t = threading.Thread(target=httpd.serve_forever)
    t.daemon = True
    t.start()