use assert[Not]IsInstance where appropriate
diff --git a/Lib/test/test_optparse.py b/Lib/test/test_optparse.py
index b11b8c9..4a380b2 100644
--- a/Lib/test/test_optparse.py
+++ b/Lib/test/test_optparse.py
@@ -348,7 +348,7 @@
 
     def test_get_option(self):
         opt1 = self.parser.get_option("-v")
-        self.assertTrue(isinstance(opt1, Option))
+        self.assertIsInstance(opt1, Option)
         self.assertEqual(opt1._short_opts, ["-v", "-n"])
         self.assertEqual(opt1._long_opts, ["--verbose", "--noisy"])
         self.assertEqual(opt1.action, "store_true")