proposition: Theorem Rezk_eta_Universal_Property : isweq (pre_composition_functor _ _ C (Rezk_eta A)).
proof: Proof. apply adj_equiv_of_cats_is_weq_of_objects. - apply is_univalent_functor_category; assumption. - apply is_univalent_functor_category; assumption. - apply Rezk_adj_equiv. Defined.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Categories.HSET.Core UniMath.CategoryTheory.Categories.HSET.Univalence UniMath.CategoryTheory.opp_precat UniMath.CategoryTheory.yoneda UniMath.CategoryTheory.Subcategory.Core UniMath.CategoryTheory.Subcategory.Full UniMath.CategoryTheory.Equivalences.Core UniMath.CategoryTheory.whiskering UniMath.CategoryTheory.precomp_fully_faithful UniMath.CategoryTheory.precomp_ess_surj