diff --git a/django/test/client.py b/django/test/client.py
index 0625f23f79..1baf6176ed 100644
--- a/django/test/client.py
+++ b/django/test/client.py
@@ -26,7 +26,8 @@ from django.utils.itercompat import is_iterable
 from django.db import transaction, close_connection
 from django.test.utils import ContextList
 
-all = ('Client', 'RequestFactory', 'encode_file', 'encode_multipart')
+__all__ = ('Client', 'RequestFactory', 'encode_file', 'encode_multipart')
+
 
 BOUNDARY = 'BoUnDaRyStRiNg'
 MULTIPART_CONTENT = 'multipart/form-data; boundary=%s' % BOUNDARY
diff --git a/django/test/testcases.py b/django/test/testcases.py
index e34262bfe5..c8f712d64b 100644
--- a/django/test/testcases.py
+++ b/django/test/testcases.py
@@ -18,6 +18,7 @@ from django.utils.functional import wraps
 __all__ = ('DocTestRunner', 'OutputChecker', 'TestCase', 'TransactionTestCase',
            'skipIfDBFeature', 'skipUnlessDBFeature')
 
+
 try:
     all
 except NameError:
diff --git a/django/test/utils.py b/django/test/utils.py
index d2649ae96b..063e30297f 100644
--- a/django/test/utils.py
+++ b/django/test/utils.py
@@ -8,9 +8,10 @@ from django.test import signals
 from django.template import Template
 from django.utils.translation import deactivate
 
-all = ('Approximate', 'ContextList', 'setup_test_environment',
+__all__ = ('Approximate', 'ContextList', 'setup_test_environment',
        'teardown_test_environment', 'get_runner')
 
+
 class Approximate(object):
     def __init__(self, val, places=7):
         self.val = val