code: def upgrade(self, flag):
          
          for pkg in self.binary:
              try:
                  subprocess.call("upgradepkg {0} {1}".format(flag, pkg),
                                  shell=True)
                  check = pkg[:-4].split("/")[-1]
                  if os.path.isfile(self.meta.pkg_path + check):
                      print("Completed!\n")
                  else:
                      raise SystemExit()
              except subprocess.CalledProcessError:
                  self._not_found("Can't upgrade", self.binary, pkg)
                  raise SystemExit(1)
docs: Upgrade Slackware binary packages with new