∀ {C₁ : Type u_1} {C₂ : Type u_2} {C₃ : Type u_3} {C₄ : Type u_4} {C₁₂ : Type u_5}
  [inst : CategoryTheory.Category.{v_1, u_1} C₁] [inst_1 : CategoryTheory.Category.{v_2, u_2} C₂]
  [inst_2 : CategoryTheory.Category.{v_3, u_3} C₃] [inst_3 : CategoryTheory.Category.{v_4, u_4} C₄]
  [inst_4 : CategoryTheory.Category.{v_5, u_5} C₁₂] (F₁₂ : CategoryTheory.Functor C₁ (CategoryTheory.Functor C₂ C₁₂))
  (G : CategoryTheory.Functor C₁₂ (CategoryTheory.Functor C₃ C₄)) {I₁ : Type u_7} {I₂ : Type u_8} {I₃ : Type u_9}
  {J : Type u_10} {r : I₁ × I₂ × I₃ → J} (ρ₁₂ : CategoryTheory.GradedObject.BifunctorComp₁₂IndexData r)
  (X₁ : CategoryTheory.GradedObject I₁ C₁) (X₂ : CategoryTheory.GradedObject I₂ C₂)
  (X₃ : CategoryTheory.GradedObject I₃ C₃)
  [inst_5 : (((CategoryTheory.GradedObject.mapBifunctor F₁₂ I₁ I₂).obj X₁).obj X₂).HasMap ρ₁₂.p]
  [inst_6 :
    (((CategoryTheory.GradedObject.mapBifunctor G ρ₁₂.I₁₂ I₃).obj
              (CategoryTheory.GradedObject.mapBifunctorMapObj F₁₂ ρ₁₂.p X₁ X₂)).obj
          X₃).HasMap
      ρ₁₂.q]
  [H : CategoryTheory.GradedObject.HasGoodTrifunctor₁₂Obj F₁₂ G ρ₁₂ X₁ X₂ X₃]
  [inst_7 :
    ((((CategoryTheory.GradedObject.mapTrifunctor (CategoryTheory.bifunctorComp₁₂ F₁₂ G) I₁ I₂ I₃).obj X₁).obj X₂).obj
          X₃).HasMap
      r],
  CategoryTheory.GradedObject.mapBifunctorComp₁₂MapObjIso F₁₂ G ρ₁₂ X₁ X₂ X₃ =
    CategoryTheory.GradedObject.mapBifunctorComp₁₂MapObjIso F₁₂ G ρ₁₂ X₁ X₂ X₃