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

Lemma prod2_comp1: forall p:point_set prod2, prod2_conv2 (prod2_conv1 p) = p.