diff --git a/pyspider/libs/base_handler.py b/pyspider/libs/base_handler.py
index d2ebe9584..781d9aa5c 100644
--- a/pyspider/libs/base_handler.py
+++ b/pyspider/libs/base_handler.py
@@ -8,7 +8,7 @@
 import sys
 import inspect
 import functools
-import fractions
+import math
 
 import six
 from six import add_metaclass, iteritems
@@ -112,7 +112,7 @@ def __new__(cls, name, bases, attrs):
         for each in attrs.values():
             if inspect.isfunction(each) and getattr(each, 'is_cronjob', False):
                 cron_jobs.append(each)
-                min_tick = fractions.gcd(min_tick, each.tick)
+                min_tick = math.gcd(min_tick, each.tick)
         newcls = type.__new__(cls, name, bases, attrs)
         newcls._cron_jobs = cron_jobs
         newcls._min_tick = min_tick