bpo-40275: Use new test.support helper submodules in tests (GH-21412)

diff --git a/Lib/test/test_locale.py b/Lib/test/test_locale.py
index 2863d20..bd08c4f 100644
--- a/Lib/test/test_locale.py
+++ b/Lib/test/test_locale.py
@@ -1,4 +1,5 @@
-from test.support import verbose, is_android, check_warnings
+from test.support import verbose, is_android
+from test.support.warnings_helper import check_warnings
 import unittest
 import locale
 import sys