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

    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()