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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(options=None, interval=None):
 """Get a stats exporter and running transport thread. Create a new `StackdriverStatsExporter` with the given options and start periodically exporting stats to stackdriver in the background. Fall back to default auth if `options` is null. This will raise `google.auth.exceptions.DefaultCredentialsError` if default credentials aren't configured. See `opencensus.metrics.transport.get_exporter_thread` for details on the transport thread. :type options: :class:`Options` :param exporter: Options to pass to the exporter :type interval: int or float :param interval: Seconds between export calls. :rtype: :class:`StackdriverStatsExporter` :return: The newly-created exporter. """

    if options is None:
        _, project_id = google.auth.default()
        options = Options(project_id=project_id)
    if str(options.project_id).strip() == "":
        raise ValueError(ERROR_BLANK_PROJECT_ID)

    ci = client_info.ClientInfo(client_library_version=get_user_agent_slug())
    client = monitoring_v3.MetricServiceClient(client_info=ci)
    exporter = StackdriverStatsExporter(client=client, options=options)

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