proposition: Lemma isaset_merely_split_epi : has_homsets C -> isaset merely_split_epi.
proof: Proof. intro. apply isaset_total2; [auto|]. intro. apply hlevelntosn, isapropishinh. Qed.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Monics UniMath.CategoryTheory.Epis UniMath.CategoryTheory.Retracts