Definition triv2 {X Y} : X -> Y -> Prop :=
fun _ _ => True.
Definition pforall {I X} (P : I -> X -> Prop) : X -> Prop :=
fun x => forall i, P i x.

Lemma state_plift2_ret_l {S X} (x : X)
(m : StateT S dist X) Pre Post P :
(forall s, state_plift (Pre s) (Post s) (P x) m) ->
state_plift2 Pre Post P (mreturn x) m.