Issue #18830: inspect.getclasstree() no more produces duplicated entries even
when input list contains duplicates.
diff --git a/Misc/NEWS b/Misc/NEWS
index 14201ca..3bbced3 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -32,6 +32,9 @@
 Library
 -------
 
+- Issue #18830: inspect.getclasstree() no more produces duplicated entries even
+  when input list contains duplicates.
+
 - Issue #18909: Fix _tkinter.tkapp.interpaddr() on Windows 64-bit, don't cast
   64-bit pointer to long (32 bits).