proposition: Lemma id_lfunE u: \1%VF u = u :> aT.
proof: Proof. exact: lfunE. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)