proposition: Lemma dot2one (F: graph2): F · 1 ≃2 F.
proof: Proof. irewrite dot2unit_r. apply add_vlabel2_mon0. Qed.
imports: HB(structures) Coq(Setoid Morphisms) mathcomp(all_ssreflect) GraphTheory(edone finite_quotient preliminaries bij equiv) GraphTheory(setoid_bigop structures pttdom mgraph ptt)