docs: def dialog_checklist(self):
          """Create checklist to choose packages for upgrade
          """
          data = []
          for upg in self.upgrade_all:
              data.append(upg[:-4])
          text = "Press 'spacebar' to unchoose packages from upgrade"
          title = " Upgrade "
          backtitle = "{0} {1}".format(self.meta.__all__,
                                       self.meta.__version__)
          status = True
          pkgs = DialogUtil(data, text, title, backtitle,
                            status).checklist()
          index = 0
          for pkg, comp, uncomp in zip(self.upgrade_all, self.comp_sum,
                                       self.uncomp_sum):
              if pkg[:-4] not in pkgs:
                  self.dwn_links.pop(index)
                  self.upgrade_all.pop(index)
                  self.comp_sum.pop(index)
                  self.uncomp_sum.pop(index)
                  self.count_upg -= 1
                  del comp, uncomp
                  index -= 1
              index += 1
          if not self.upgrade_all:
              raise SystemExit()