def METHOD_NAME(self, event):
    index = self.listbox.index("active")
    if self.listbox.selection_includes(index):
        index = index - 1
    else:
        index = self.listbox.size() - 1
    if index < 0:
        self.listbox.bell()
    else:
        self.select(index)
        self.on_select(index)
    return "break"