Interface DataflowGraphCluster

If the cluster contains unknown side effects

All nodes that are part of this cluster

The node which started the cluster, as this is theoretically picked random, there are just two guarantees you can rely on:

1. The node is part of the members as well
2. At one point during the clustering, the node wsa considered as a starting point

In general, this is more of a debugging aid/representative of the cluster.