Although the default policy calculation for the job overall status is already defined, for some facilities, this behavior may need to be overridden. By taking the $subjob and $agenda status information (these are strings like "complete", "killed", and "failed"), the function is allowed to calculate what the job overall 's overall status value will be. Be very careful that the function actually return values which make sense, as the function can mark jobs in any way it wants, even with invalid status values.