f(p)
i1 : X = specialCubicFourfold surface {3,4}; o1 : ProjectiveVariety, cubic fourfold containing a surface of degree 5 and sectional genus 1
i2 : f = detectCongruence(X,1); o2 : Congruence of 2-secant lines to surface in PP^5
i3 : C = f point ambient X; o3 : ProjectiveVariety, curve in PP^5
i4 : member(C,f) o4 = true
i5 : assert oo