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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 _ForemanOp(self):
 """Sends Foreman checks periodically."""

    period = config.CONFIG["Client.foreman_check_frequency"]
    self._threads["Worker"].SendReply(
        rdf_protodict.DataBlob(),
        session_id=rdfvalue.FlowSessionID(flow_name="Foreman"),
        require_fastpoll=False)
    time.sleep(period)