diff --git a/chinadns/dnsrelay.py b/chinadns/dnsrelay.py
index ffeb719..26410ea 100644
--- a/chinadns/dnsrelay.py
+++ b/chinadns/dnsrelay.py
@@ -29,14 +29,15 @@
 import struct
 import logging
 
+import argparse
+from shadowsocks import eventloop, asyncdns, lru_cache, common
+
 info = sys.version_info
+
 if not (info[0] == 2 and info[1] >= 7):
     print 'Python 2.7 required'
     sys.exit(1)
 
-import argparse
-from shadowsocks import eventloop, asyncdns, lru_cache
-
 
 BUF_SIZE = 16384
 
@@ -92,7 +93,7 @@ def _parse_hosts(self):
                     parts = line.split()
                     if len(parts) >= 2:
                         ip = parts[0]
-                        if asyncdns.is_ip(ip):
+                        if common.is_ip(ip):
                             for i in xrange(1, len(parts)):
                                 hostname = parts[i]
                                 if hostname:
diff --git a/test.py b/test.py
index ae12d00..f0a3175 100755
--- a/test.py
+++ b/test.py
@@ -2,12 +2,14 @@
 # -*- coding: utf-8 -*-
 
 import sys
-sys.path.insert(0, 'shadowsocks')
 import os
 import signal
 import select
+
 from subprocess import Popen, PIPE
 
+sys.path.insert(0, 'shadowsocks')
+
 with open(sys.argv[-1]) as f:
     dig_cmd = f.read()
 p1 = Popen(['sudo', sys.executable, 'chinadns/dnsrelay.py'], shell=False,