∀ {α : Type u_1} [inst : DecidableEq α] [inst_1 : Fintype α] {δ : α → Type u_2} [inst_2 : (a : α) → DecidableEq (δ a)]
  (t : (a : α) → Finset (δ a)) (a : α), ∀ x ∉ t a, {f ∈ Fintype.piFinset t | f a = x} = ∅