Patch #1413711: Certain patterns of differences were making difflib
touch the recursion limit. The applied patch inlines the recursive
__helper method in a non-recursive way.
diff --git a/Misc/NEWS b/Misc/NEWS
index 830583c..484b50a 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -676,6 +676,9 @@
 
 - ` uu.encode()`` and ``uu.decode()`` now support unicode filenames.
 
+- Patch #1413711: Certain patterns of differences were making difflib
+  touch the recursion limit.
+
 Build
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