proposition: Lemma Pr_set1 a : Pr [set a] = P a.
proof: Proof. by rewrite /Pr big_set1. 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