Fix formatter usage of filter(). Bug #3800.
diff --git a/Misc/NEWS b/Misc/NEWS
index 7dde481..d22d038 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -96,6 +96,8 @@
 Library
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+- Issue #3800: fix filter() related bug in formatter.py.
+
 - Issue #874900: fix behaviour of threading module after a fork.
 
 - Issue #3535: zipfile couldn't read some zip files larger than 2GB.