GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
# S1 with C2-iso and a point of S3-iso M := [ [1,2], [1,3], [2,3] ]; G := Group( (1,2) ); S3 := Group( (1,2), (1,2,3) ); iso := rec( 1 := S3, 2 := G, 3 := G ); mu := []; dim := 5;