{C : Type u₁} →
  [inst : CategoryTheory.Category.{v₁, u₁} C] →
    {D : Type u₂} →
      [inst_1 : CategoryTheory.Category.{v₂, u₂} D] →
        CategoryTheory.Functor C D → CategoryTheory.Functor (CategoryTheory.Skeleton C) (CategoryTheory.Skeleton D)