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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(service_name, hostname=None, endpoint=None, interval=None):
 """Create a new worker thread and attach the exporter to it. :type endpoint: str :param endpoint: address of the opencensus service. :type service_name: str :param service_name: name of the service :type host_name: str :param host_name: name of the host (machine or host name) :type interval: int or float :param interval: Seconds between export calls. """

    endpoint = utils.DEFAULT_ENDPOINT if endpoint is None else endpoint
    exporter = StatsExporter(
        ExportRpcHandler(_create_stub(endpoint), service_name, hostname))

    transport.get_exporter_thread(stats.stats, exporter, interval)
    return exporter