Lemma isaset_invertible_2cell {C : bicat} {X Y : C} (f g : X --> Y) : isaset (invertible_2cell f g). Proof. use isaset_total2. - apply C. - intro. apply isasetaprop. apply isaprop_is_invertible_2cell. Qed.
Require Import UniMath.Foundations.All. Require Import UniMath.MoreFoundations.All. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.Bicategories.Core.Bicat. Import Bicat.Notations.