fact: Definition sup_proper_u : forall {Ix : Type} (f g : Ix -> A), (forall (i : Ix), L.eq (f i) (g i)) -> L.eq (sup f) (sup g).
imports: SetoidClass Coq.Classes.Morphisms Coq.Arith.PeanoNat Fiat.Common.Coq__8_4__8_5__Compat