Definition thetahat_0 (Z : Ptd) (f : [C, C] ⟦ U Z, U (ptd_from_alg InitAlg) ⟧): EndEndC ⟦ BinCoproductObject (CPEndEndC (constant_functor [C, C] [C, C] (U Z)) (functor_fix_snd_arg [C, C] Ptd [C, C] (θ_source H) Z)), BinCoproductObject (CPEndEndC (constant_functor [C, C] [C, C] (pr1 InitAlg)) (functor_fix_snd_arg [C, C] Ptd [C, C] (θ_target H) Z)) ⟧ . Proof. exact (BinCoproductOfArrows EndEndC (CPEndEndC _ _) (CPEndEndC _ _) (constant_nat_trans _ _ _ _ f) (θ_in_first_arg Z)). Defined.
Require Import UniMath.Foundations.PartD. Require Import UniMath.MoreFoundations.PartA. Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.NaturalTransformations. Require Import UniMath.CategoryTheory.whiskering. Require Import UniMath.CategoryTheory.Monads.Monads. Require Import UniMath.CategoryTheory.Limits.BinProducts. Require Import UniMath.CategoryTheory.Limits.BinCoproducts. Require Import UniMath.CategoryTheory.Limits.Initial. Require Import UniMath.CategoryTheory.FunctorAlgebras. Require Import UniMath.CategoryTheory.opp_precat. Require Import UniMath.CategoryTheory.yoneda. Require Import UniMath.CategoryTheory.Categories.HSET.Core. Require Import UniMath.CategoryTheory.PointedFunctors. Require Import UniMath.CategoryTheory.PrecategoryBinProduct. Require Import UniMath.CategoryTheory.HorizontalComposition. Require Import UniMath.CategoryTheory.PointedFunctorsComposition. Require Import UniMath.SubstitutionSystems.Signatures. Require Import UniMath.SubstitutionSystems.SimplifiedHSS.SubstitutionSystems. Require Import UniMath.SubstitutionSystems.GenMendlerIteration. Require Import UniMath.CategoryTheory.RightKanExtension. Require Import UniMath.SubstitutionSystems.GenMendlerIteration. Require Import UniMath.CategoryTheory.BicatOfCatsElementary. Require Import UniMath.SubstitutionSystems.Notation.