Issue #9509: make argarse properly handle IOErrors raised by argparse.FileType. Approved by Georg in the tracker.
diff --git a/Misc/NEWS b/Misc/NEWS
index f77b603..42ce636 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -140,6 +140,9 @@
   OSError exception when The OS had been told to ignore SIGCLD in our process
   or otherwise not wait for exiting child processes.
 
+- Issue #9509: argparse now properly handles IOErrors raised by
+  argparse.FileType.
+
 Extension Modules
 -----------------