public static <E, F> AbstractGroupExpression<E, List<F>> list(GroupExpression<E, F> groupExpression) {
        return new MixinGroupExpression<E, F, List<F>>(groupExpression, new GList<F>(groupExpression));
    }
Create a new aggregating list expression

@param groupExpression values for this expression will be accumulated into a list
@param <E>
@param <F>
@return wrapper expression
querydsl-core/src/main/java/com/querydsl/core/group/GroupBy.java