Global Instance Pred_Dist_Lift : PredLift dist :=
{|
plift := @dist_lift;
plift_ret := dist_lift_ret;
plift_bind := dist_lift_bind;
plift_weaken := @dist_lift_weaken;
plift_split := @dist_split;
plift_true := @dist_true;
plift_comm := @dist_comm;
|}.

Lemma coin_flip_triv :
plift (fun _ => True) coin_flip.