diff --git a/flask/testsuite/helpers.py b/flask/testsuite/helpers.py
index c645dc14..b765528b 100644
--- a/flask/testsuite/helpers.py
+++ b/flask/testsuite/helpers.py
@@ -265,8 +265,9 @@ class SendfileTestCase(FlaskTestCase):
             # etags
             self.assert_equal(len(captured), 1)
             with catch_warnings() as captured:
-                from StringIO import StringIO as PYStringIO
-                f = PYStringIO('Test')
+                class PyStringIO(StringIO):
+                    pass
+                f = PyStringIO('Test')
                 f.name = 'test.txt'
                 rv = flask.send_file(f)
                 rv.direct_passthrough = False
diff --git a/flask/testsuite/testing.py b/flask/testsuite/testing.py
index de78746b..11ab763b 100644
--- a/flask/testsuite/testing.py
+++ b/flask/testsuite/testing.py
@@ -207,8 +207,8 @@ class TestToolsTestCase(FlaskTestCase):
         with app.test_client() as c:
             rv = c.post('http://domain.com/action?vodka=42', data={'gin': 43})
             self.assert_equal(rv.status_code, 200)
-            self.assert_('gin' in flask.request.form)
-            self.assert_('vodka' in flask.request.args)
+            self.assert_true('gin' in flask.request.form)
+            self.assert_true('vodka' in flask.request.args)
 
 
 class SubdomainTestCase(FlaskTestCase):