fact: Record PreGraph {EV: EqDec Vertex eq} {EE: EqDec Edge eq} := { vvalid : Ensemble Vertex; evalid : Ensemble Edge; src : Edge -> Vertex; dst : Edge -> Vertex }.
imports: Coq.Logic.ProofIrrelevance CertiGraph.lib.Ensembles_ext CertiGraph.lib.EquivDec_ext CertiGraph.lib.List_ext CertiGraph.lib.relation_list CertiGraph.lib.Equivalence_ext