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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 _flow_check_handler(self):
 """Top level routine to check OVS flow consistency. """

        LOG.info("In _flow_check_handler")
        try:
            with self.ovs_vdp_lock:
                self._flow_check_handler_internal()
        except Exception as e:
            LOG.error("Exception in _flow_check_handler_internal %s",
                      str(e))