proposition: Lemma set_incl_in_eq : forall E F, (E \c F) = (forall x, x \in E -> x \in F).
proof: Proof. Proof using. apply incl_in_eq. Qed.
imports: Coq.Classes.Morphisms TLC(LibTactics LibLogic LibReflect LibList LibOperation LibMonoid LibInt LibNat LibEpsilon LibRelation LibMin)