fact: Definition is_invertible_2cell_to_is_nat_z_iso {C D : bicat_of_cats} {F G : C --> D} (η : F ==> G) : is_invertible_2cell η → is_nat_z_iso (pr1 η).
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.whiskering UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.FunctorCategory UniMath.CategoryTheory.HorizontalComposition UniMath.CategoryTheory.PrecategoryBinProduct UniMath.Bicategories.Core.Bicat