Inductive twoT := | twoT_1 | twoT_2.Inductive twoT := | twoT_1 | twoT_2.Inductive twoT := | twoT_1 | twoT_2.

(* Specifications: *)
Lemma prod2_comp1: forall p:point_set prod2, prod2_conv2 (prod2_conv1 p) = p.
Lemma prod2_comp2: forall p:point_set X * point_set Y, prod2_conv1 (prod2_conv2 p) = p.