add : blurb added.

Author: sadrasabouri

Misc/NEWS.d/next/Core_and_Builtins/2026-05-18-16-20-18.gh-issue-47169.kE86QZ.rst

@@ -0,0 +1,7 @@
+OSError.__str__() now includes the symbolic name of the error code (e.g.
+[Errno 2] is now shown as [Errno 2 (ENOENT)]) alongside the numeric value.
+The errno definitions were moved from errnomodule.c to a header file in
+Objects/ so they are accessible to the exception machinery. A new
+OSError_format_errno function searches this header directly at error time to
+resolve the symbolic name and render the error output. The numeric value is
+preserved for backward compatibility.