proposition: Lemma isaprop_is_iso {C : precategory_data} (a b : C) (f : a --> b) : isaprop (is_iso f).
proof: Proof. apply impred; intro. apply isapropisweq. Qed.
imports: UniMath.Foundations.PartA UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories