Handling of "any" in ConditionSet does not fit the model

In ConditionSet class the "any" property is not a simple Set, but a Set of Sets:

private final Set<? extends Set<ConditionName>> any;

It seems not to fit the YANG model, where all 3 condition subsets (all, any, none) are just lists:

grouping has-conditions {
list condition {
description
"...";

key "name";
leaf name

uses label;
}
}