Definition functor_opp_data {C D : precategory} (F : functor C D) : functor_data C^op D^op := tpair (fun F : C^op -> D^op => ∏ a b, C^op ⟦a, b⟧ -> D^op ⟦F a, F b⟧) F (fun (a b : C) (f : C⟦b, a⟧) => functor_on_morphisms F f).
Require Import UniMath.Foundations.PartD. Require Import UniMath.Foundations.Propositions. Require Import UniMath.MoreFoundations.All. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.Core.NaturalTransformations. Require Import UniMath.CategoryTheory.Core.Univalence. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.Setcategories. Require Import UniMath.CategoryTheory.FunctorCategory.