fact: Record graph2 Lv Le := Graph2 { graph_of:> graph Lv Le; input: graph_of; output: graph_of }.
imports: HB(structures) Coq(Setoid Morphisms) mathcomp(all_ssreflect) GraphTheory(edone finite_quotient preliminaries bij equiv) GraphTheory(setoid_bigop structures pttdom mgraph ptt)