fact: Definition lift_dlet1_prod A B C D1 D2 := @lift_dlet1 A B C (D1 * D2).
imports: Coq.ZArith.ZArith Coq.Lists.List Coq.Setoids.Setoid Coq.Classes.Morphisms Coq.QArith.QArith_base Coq.QArith.Qreduction Coq.QArith.Qround