Issue #17883: Backport test.test_support._is_gui_available()
This should stop the Windows buildbots from hanging on test_ttk_guionly.
diff --git a/Misc/NEWS b/Misc/NEWS
index 12bfafb..22be7c4 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -23,6 +23,9 @@
Tests
-----
+- Issue #17883: Backported _is_gui_available() in test.test_support to
+ avoid hanging Windows buildbots on test_ttk_guionly.
+
- Issue #18702: All skipped tests now reported as skipped.
- Issue #19085: Added basic tests for all tkinter widget options.