code: def add_policy(self, name, policy_type, cooldown, change=None,
              is_percent=False, desired_capacity=None, args=None):
          
          return self.manager.add_policy(self, name, policy_type, cooldown,
                  change=change, is_percent=is_percent,
                  desired_capacity=desired_capacity, args=args)
docs: Adds a policy with the given values to this scaling group. The
          'change' parameter is treated as an absolute amount, unless
          'is_percent' is True, in which case it is treated as a percentage.