Global Instance option_Serializer : Serializer (option A).Definition pair_serialize (x : A * B) : IOStreamWriter.t :=
    let (a, b) := x in IOStreamWriter.append (fun _ => serialize a)
                                     (fun _ => serialize b).

(* Specifications: *)
Lemma pair_serialize_deserialize_id : serialize_deserialize_id_spec pair_serialize pair_deserialize.