{α : Type u_1} →
  {β : Type u_2} →
    (motive : Lean.AssocList α β → Sort u_3) →
      (x : Lean.AssocList α β) →
        (Unit → motive Lean.AssocList.nil) →
          ((a : α) → (b : β) → (es : Lean.AssocList α β) → motive (Lean.AssocList.cons a b es)) → motive x