def _confirm_launched_at(self, block, exists):
        if exists.get('state') <= 'active':
            return

        apb, ape = self._get_audit_period(exists)

        # Does launched_at have a value within this audit period?
        # If so, we should have a related event. Otherwise, this
        # instance was created previously.
        launched_at = self._extract_launched_at(exists)
        if apb and ape and apb <= launched_at <= ape and len(block) == 0:
            raise UsageException("U8", ".exists launched_at in audit "
                                       "period, but no related events found.")

            # TODO(sandy): Confirm the events we got set launched_at
            # properly.
dataset/ETHPy150Open openstack/stacktach-winchester/winchester/pipeline_handler.py/UsageHandler._confirm_launched_at/operator `!=` -> `<=`