proposition: Lemma galoisClosure_id E F : galois E F -> normalClosure E F = F.
proof: Proof. by move=> /and3P[EF _ /normalClosure_id->]. Qed.
imports: HB(structures) mathcomp(all_ssreflect all_fingroup all_algebra) mathcomp(all_solvable all_field) Abel(various char0)