complain if the codec doesn't return unicode
diff --git a/Misc/NEWS b/Misc/NEWS
index fe793e8..7fff780 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -9,6 +9,9 @@
 Core and Builtins
 -----------------
 
+- Raise a better error when non-unicode codecs are used for a file's coding
+  cookie.
+
 - Issue #17976: Fixed potential problem with file.write() not detecting IO error
   by inspecting the return value of fwrite().  Based on patches by Jaakko Moisio
   and Victor Stinner.