proposition: Lemma unfold_Z_div_neg_neg x y : Z.div (Z.neg x) (Z.neg y) = Z_div_unfolded (Z.neg x) (Z.neg y).
proof: Proof. reflexivity. Qed.
imports: Coq.ZArith.ZArith Coq.Lists.List Coq.Setoids.Setoid Coq.Classes.Morphisms Coq.QArith.QArith_base Coq.QArith.Qreduction Coq.QArith.Qround