fact: Definition cpr_eq (X : {RV P -> A}) (a : A) (Y : {RV P -> B}) (b : B) := locked (`Pr_P[ finset (X @^-1 a) | finset (Y @^-1 b)]).
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