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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 new_stats_exporter(option):
 """ new_stats_exporter returns an exporter that exports stats to Prometheus. """

    if option.namespace == "":
        raise ValueError("Namespace can not be empty string.")

    collector = new_collector(option)

    exporter = PrometheusStatsExporter(options=option,
                                       gatherer=option.registry,
                                       collector=collector)
    return exporter