docstring reference to another docstring

[bdb112]

A function of the class ClusterSet uses a similar function of the
class Cluster to do most of its work.  Its docstring could have so
much in common with that in Cluster that it could be just a line or
two in addition to that of Cluster.

Is there a way for the ClusterSet docstring to tack the Cluster
docstring onto itself, rather than simply saying "See docstring for
Cluster"?