proposition: Lemma pmap_eqdep_sym A G G' h h' : @pmap_eqdep A G h G' h' -> pmap_eqdep h' h.
proof: Proof. by case. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype path fingraph) fourcolor(hypermap geometry color coloring cfmap ctree)