// Set partitions of a given shape
setPartitionsLambda:=function(n,lambda)
 G:=Sym(n);
 x:={ Seqset(y) : y in Partition([1..n],lambda) };
 return Setseq(Orbit(G,x));
end function;
 
// Set partitions of all shapes
setPartitions:=func< n | &cat[ setPartitionsLambda(n,l) : l in Partitions(n) ] >;

// Example
setPartitions(3);