Issue #10188 (partial resolution): tidy up some behaviour in the new tempfile.TemporaryDirectory context manager
diff --git a/Lib/test/support.py b/Lib/test/support.py
index 2fd019a..27efd37 100644
--- a/Lib/test/support.py
+++ b/Lib/test/support.py
@@ -874,6 +874,9 @@
 def captured_stdout():
     return captured_output("stdout")
 
+def captured_stderr():
+    return captured_output("stderr")
+
 def captured_stdin():
     return captured_output("stdin")