∀ {C : Type u_1} [inst : CategoryTheory.Category.{u_4, u_1} C] {V : Type u_3}
  [inst_1 : CategoryTheory.Category.{u_2, u_3} V] [inst_2 : CategoryTheory.MonoidalCategory C]
  [inst_3 : CategoryTheory.MonoidalCategory V] {F G : CategoryTheory.MonoidalCategory.DayFunctor C V}
  (natTrans natTrans_1 : F.functor ⟶ G.functor),
  { natTrans := natTrans }.natTrans = { natTrans := natTrans_1 }.natTrans →
    { natTrans := natTrans } = { natTrans := natTrans_1 }