bpo-40275: Use new test.support helper submodules in tests (GH-21151)

Use new test.support helper submodules in tests:

* distutils tests
* test_buffer
* test_compile
* test_filecmp
* test_fileinput
* test_readline
* test_smtpnet
* test_structmembers
* test_tools
diff --git a/Lib/test/test_compile.py b/Lib/test/test_compile.py
index 566ca27..3dd8c8d 100644
--- a/Lib/test/test_compile.py
+++ b/Lib/test/test_compile.py
@@ -7,7 +7,9 @@
 import tempfile
 import types
 from test import support
-from test.support import script_helper, FakePath
+from test.support import script_helper
+from test.support.os_helper import FakePath
+
 
 class TestSpecifics(unittest.TestCase):