∀ (R : Type u₁) {L : Type u₂} [inst : CommRing R] [inst_1 : LieRing L] [inst_2 : LieAlgebra R L] {A : Type u₃}
  [inst_3 : Ring A] [inst_4 : Algebra R A] (f : L →ₗ⁅R⁆ A) (g : UniversalEnvelopingAlgebra R L →ₐ[R] A),
  ⇑g ∘ ⇑(UniversalEnvelopingAlgebra.ι R) = ⇑f ↔ g = (UniversalEnvelopingAlgebra.lift R) f