docs: def terminate(self, arg):
          """
          Terminate instance with given EC2 ID or nametag.
          """
          instance = self.get(arg)
          with self.msg("Terminating %s (%s): " % (instance.name, instance.id)):
              instance.rename("old-%s" % instance.name)
              instance.terminate()
              while instance.state != 'terminated':
                  time.sleep(5)
                  self.log(".", end='')
                  instance.update()