proposition: Lemma isaset_cells_prebicat_of_cats : isaset_cells prebicat_of_cats.
proof: Proof. intros a b f g. apply isaset_nat_trans. apply homset_property. Defined.
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