fact: Definition isotoid_2_1 {C : bicat} (HC : is_univalent_2_1 C) {a b : C} {f g : C⟦a,b⟧} (α : invertible_2cell f g) : f = g := invmap (idtoiso_2_1 f g ,, HC a b f g) α.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Groupoids UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Core.Isos UniMath.Bicategories.Core.Bicat UniMath.Bicategories.Core.Unitors UniMath.Bicategories.Core.Invertible_2cells UniMath.Bicategories.Morphisms.Adjunctions UniMath.Bicategories.Core.BicategoryLaws