presto-main/src/main/java/io/prestosql/execution/scheduler/FixedSourcePartitionedScheduler.java/FixedSourcePartitionedScheduler/partitionHandleFor
class FixedSourcePartitionedScheduler:    private ConnectorPartitionHandle partitionHandleFor(Lifespan lifespan)
    {
        if (lifespan.isTaskWide()) {
            return NOT_PARTITIONED;
        }
        return partitionHandles.get(lifespan.getId());
    }