How to highlight everything in tkinter checklist?

Question

Python

how do i select all child elements if i check the box of the parent "Country"

cheсklistCountry = tix.CheckList(root, browsecmd='selectItem', width=300, height=350)
    cheсklistCountry.place(x=5, y=27)
    cheсklistCountry.hlist.header_create(0, itemtype=tix.TEXT, text='Страна:',relief='flat')
    cheсklistCountry.hlist.add("Country", text="Страны")
    cheсklistCountry.setstatus("Country", "off")
    for country in short_country_list:
        index = short_country_list.index(country)
        NameParam = "Country.Item" + str(index)
        cheсklistCountry.hlist.add(NameParam, text=country)
        cheсklistCountry.setstatus(NameParam, "off")