def test_filter_ips_white_list(self):
        CONF.network_label_regex = '.*'
        CONF.ip_regex = '^(15.|123.)'
        CONF.black_list_regex = '^10.123.123.*'
        ip = self.instance.get_visible_ip_addresses()
        ip = filter_ips(
            ip, CONF.ip_regex, CONF.black_list_regex)
        self.assertEqual(2, len(ip))
        self.assertTrue('123.123.123.123' in ip)
        self.assertTrue('15.123.123.123' in ip)
def dfs(self, num, target, pos, cur_str, cur_val, mul, ret):
        if pos >= len(num):
            if cur_val == target:
                ret.append(cur_str)
        else:
            for i in xrange(pos, len(num)):
                if i != pos and num[pos] == "0":
                    continue
                nxt_val = int(num[pos:i+1])

                if not cur_str:
                    self.dfs(num, target, i+1, "%d"%nxt_val, nxt_val, nxt_val, ret)
                else:
                    self.dfs(num, target, i+1, cur_str+"+%d"%nxt_val, cur_val+nxt_val, nxt_val, ret)
                    self.dfs(num, target, i+1, cur_str+"-%d"%nxt_val, cur_val-nxt_val, -nxt_val, ret)
                    self.dfs(num, target, i+1, cur_str+"*%d"%nxt_val, cur_val-mul+mul*nxt_val, mul*nxt_val, ret)