proposition: Lemma ValidDGTree_1: forall p bl ep f m dg, ValidDGTree p bl ep f m dg -> exists dgs, dg = DGNode f dgs.
proof: Proof. intros. inversion H. exists dgs. trivial. Qed.
imports: Coq(List) JML(Stack) Coq(ListSet) Coq(Bool) Coq(ZArith) Coq(Relation_Operators) JML(ListHelpers) Coq(Classical) Coq(DecidableType) Coq(FSetInterface) Coq(FSetProperties) Coq(FSetEqProperties) Coq(FSetFacts) Coq(Sumbool) Coq(Lia)