proposition: Lemma cong_identity : cong_identityP Point cong'.
proof: Proof. by rewrite /cong'; move=> a b _ /eqP ab_eq. Qed.
imports: mathcomp.ssreflect.ssreflect mathcomp(ssrbool ssrfun ssrnat eqtype choice seq) mathcomp(fintype finset finfun bigop order) mathcomp(ssralg ssrnum path generic_quotient matrix mxalgebra) mathcomp(zmodp) mathcomp(tuple fintype bigop) GeoCoq.Meta_theory.Models.POF_to_Tarski GeoCoq.Meta_theory.Counter_models.Planar.independence