diff --git a/tests/test_requests_ext.py b/tests/test_requests_ext.py
index 883bdceb..7645d8c1 100644
--- a/tests/test_requests_ext.py
+++ b/tests/test_requests_ext.py
@@ -110,7 +110,7 @@ class RequestsTestSuite(unittest.TestCase):
         s = requests.session()
         s.get(url='http://tinyurl.com/preview.php?disable=1')
         # we should have set a cookie for tinyurl: preview=0
-        self.assertIn('preview', s.cookies)
+        self.assertTrue('preview' in s.cookies)
         self.assertEqual(s.cookies['preview'], '0')
         self.assertEqual(list(s.cookies)[0].name, 'preview')
         self.assertEqual(list(s.cookies)[0].domain, 'tinyurl.com')
@@ -118,13 +118,13 @@ class RequestsTestSuite(unittest.TestCase):
         # get cookies on another domain
         r2 = s.get(url='http://httpbin.org/cookies')
         # the cookie is not there
-        self.assertNotIn('preview', json.loads(r2.text)['cookies'])
+        self.assertTrue('preview' not in json.loads(r2.text)['cookies'])
 
         # this redirects to another domain, httpbin.org
         # cookies of the first domain should NOT be sent to the next one
         r3 = s.get(url='http://tinyurl.com/7zp3jnr')
         assert r3.url == 'http://httpbin.org/cookies'
-        self.assertNotIn('preview', json.loads(r2.text)['cookies'])
+        self.assertTrue('preview' not in json.loads(r2.text)['cookies'])
 
 if __name__ == '__main__':
     unittest.main()