proposition: Lemma pr_eq_pairCA a b c : `Pr[ [% TX, [%TY, TZ]] = (a, (b, c)) ] = `Pr[ [% TY, [% TX, TZ]] = (b, (a, c))].
proof: Proof. by rewrite !pr_eqE; apply eq_bigl => u; rewrite !inE /= !xpair_eqE andbCA. Qed.
imports: mathcomp(all_ssreflect ssralg ssrnum matrix) mathcomp(Rstruct reals) Reals Lra ssrR Reals_ext realType_ext logb ssr_ext ssralg_ext bigop_ext fdist