swap -- swap the order of the two special surfaces

i1 : S = random({3:{1}},0_(PP_(ZZ/65521)^5));

o1 : ProjectiveVariety, surface in PP^5

i2 : T = random S;

o2 : ProjectiveVariety, surface in PP^5

i3 : X = specialFourfold (S & T);

o3 : ProjectiveVariety, cubic fourfold in C_8 containing two planes

i4 : surfaces X

o4 = (S, T)

o4 : Sequence

i5 : Y = swap X;

o5 : ProjectiveVariety, cubic fourfold in C_8 containing two planes

i6 : surfaces Y

o6 = (T, S)

o6 : Sequence

i7 : assert(X == Y)