∀ {C : Type u₁} [inst : CategoryTheory.Category.{v₁, u₁} C] [inst_1 : CategoryTheory.Preadditive C] {D : Type u₁}
  [inst_2 : CategoryTheory.Category.{v₁, u₁} D] [inst_3 : CategoryTheory.Preadditive D]
  [inst_4 : CategoryTheory.Limits.HasFiniteBiproducts D] (F : CategoryTheory.Functor C D) [inst_5 : F.Additive]
  {X Y : CategoryTheory.Mat_ C} (f : X ⟶ Y),
  (CategoryTheory.Mat_.lift F).map f = CategoryTheory.Limits.biproduct.matrix fun i j => F.map (f i j)