proposition: Lemma npe_refl: forall (m: NodePred Vertex), node_pred_equiv m m.
proof: Proof. unfold node_pred_equiv; intros. tauto. Qed.
imports: Coq.Logic.ProofIrrelevance CertiGraph.lib.Ensembles_ext CertiGraph.lib.EquivDec_ext CertiGraph.lib.List_ext CertiGraph.lib.relation_list CertiGraph.lib.Equivalence_ext