diff --git a/gcloud/test__helpers.py b/gcloud/test__helpers.py
index 1285776c06da..96e524d9d428 100644
--- a/gcloud/test__helpers.py
+++ b/gcloud/test__helpers.py
@@ -166,13 +166,15 @@ def tearDown(self):
 
     def test_success(self):
         import os
-        import tempfile
-        with tempfile.NamedTemporaryFile(mode='w') as credential_file:
-            credential_file.write('{"project_id": "test-project-id"}')
-            credential_file.seek(0)
-            os.environ['GOOGLE_APPLICATION_CREDENTIALS'] = credential_file.name
+        from gcloud._testing import _NamedTemporaryFile
+
+        with _NamedTemporaryFile() as temp:
+            with open(temp.name, mode='w') as creds_file:
+                creds_file.write('{"project_id": "test-project-id"}')
+                creds_file.seek(0)
+                os.environ['GOOGLE_APPLICATION_CREDENTIALS'] = creds_file.name
 
-            self.assertEqual('test-project-id', self._callFUT())
+                self.assertEqual('test-project-id', self._callFUT())
 
     def test_no_environment(self):
         self.assertEqual(None, self._callFUT())