Lemma contr_cat_fully_faithful_to_isiso {F : functor C D} (ff : fully_faithful F) : is_catiso F. Proof. use make_dirprod; [assumption|]. apply isweqcontrcontr; apply contr_cat_iscontr. Defined.
Require Import UniMath.Foundations.Preamble. Require Import UniMath.MoreFoundations.PartA. Require Import UniMath.Algebra.Groups. Require Import UniMath.Algebra.RigsAndRings. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.NaturalTransformations. Require Import UniMath.CategoryTheory.catiso. Require Import UniMath.CategoryTheory.Additive. Require Import UniMath.CategoryTheory.CategoriesWithBinOps. Require Import UniMath.CategoryTheory.PreAdditive. Require Import UniMath.CategoryTheory.PrecategoriesWithAbgrops. Require Import UniMath.CategoryTheory.Categories.HSET.Core.