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.