proposition: Lemma fieldP : Field.axiom U.
proof: Proof. by move=> u; rewrite -(inj_eq val_inj) rmorph0 -unitfE subfield_subproof. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat div seq) mathcomp(choice fintype finfun bigop prime binomial)