∀ {α : Type u_1} {M : Type u_8} {N : Type u_10} {P : Type u_11} [inst : AddZeroClass M] [inst_1 : AddCommMonoid N]
  [inst_2 : AddCommMonoid P] (g : N →+ P) (f : α → M →+ N),
  g.comp (Finsupp.liftAddHom f) = Finsupp.liftAddHom fun a => g.comp (f a)