∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] [inst_1 : CategoryTheory.Limits.HasBinaryProducts C]
  (P Q R : C),
  (CategoryTheory.Limits.prod.associator P Q R).hom =
    CategoryTheory.Limits.prod.lift
      (CategoryTheory.CategoryStruct.comp CategoryTheory.Limits.prod.fst CategoryTheory.Limits.prod.fst)
      (CategoryTheory.Limits.prod.lift
        (CategoryTheory.CategoryStruct.comp CategoryTheory.Limits.prod.fst CategoryTheory.Limits.prod.snd)
        CategoryTheory.Limits.prod.snd)