i1 : phi = (specialCubicTransformation(2,ZZ/33331))!;
o1 : RationalMap (cubic birational map from PP^3 to hypersurface in PP^4)

i2 : str = toExternalString phi;

i3 : #str
o3 = 6927

i4 : time phi' = value str;
 used 0.0709218 seconds
o4 : RationalMap (cubic birational map from PP^3 to hypersurface in PP^4)

i5 : time describe phi'
 used 0.0196343 seconds
o5 = rational map defined by forms of degree 3
source variety: PP^3
target variety: smooth quadric hypersurface in PP^4
dominance: true
birationality: true (the inverse map is already calculated)
projective degrees: {1, 3, 4, 2}
number of minimal representatives: 1
dimension base locus: 1
degree base locus: 5
coefficient ring: ZZ/33331

i6 : time describe inverse phi'
 used 0.0107821 seconds
o6 = rational map defined by forms of degree 2
source variety: smooth quadric hypersurface in PP^4
target variety: PP^3
dominance: true
birationality: true (the inverse map is already calculated)
projective degrees: {2, 4, 3, 1}
number of minimal representatives: 1
dimension base locus: 1
degree base locus: 5
coefficient ring: ZZ/33331
