fact: Definition Opposite_Functor `(F : C ⟶ D) : C^op ⟶ D^op := @Build_Functor (C^op) (D^op) F (λ (x y : C ^op) (f : x ~{ C ^op }~> y), @fmap C D F y x f) (λ (x y : C ^op) (f g : x ~{ C ^op }~> y), @fmap_respects _ _ F y x f g) (λ x : C ^op, fmap_id) (λ (x y z : C ^op) (f : y ~{ C ^op }~> z) (g : x ~{ C ^op }~> y), @fmap_comp _ _ F _ _ _ g f).
imports: Category.Lib Category.Theory.Category Category.Theory.Functor Category.Construction.Opposite