∀ (C : Type u_2) [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.Preadditive C]
  (F : CategoryTheory.Functor C C) [F.Additive] (A₁ A₂ : CategoryTheory.Endofunctor.Algebra F) (α : A₁ ⟶ A₂),
  CategoryTheory.CategoryStruct.comp (F.map (-α.f)) A₂.str = CategoryTheory.CategoryStruct.comp A₁.str (-α.f)