From caa54419fd16f26ef9ba317dc02c7ed84bcdffe1 Mon Sep 17 00:00:00 2001
From: qudongfang <qudongfang@users.noreply.github.com>
Date: Mon, 18 May 2020 04:50:51 +0100
Subject: [PATCH] bpo-40651: Improve LRU recipe in the OrderedDict
 documentation  (GH-GH-20139) (cherry picked from commit
 bb8635cc3bc3dd65996803849ee1a91cfbebae9c)

Co-authored-by: qudongfang <qudongfang@users.noreply.github.com>
---
 Doc/library/collections.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst
index 8dcf9451d72bfe..d4297166597b64 100644
--- a/Doc/library/collections.rst
+++ b/Doc/library/collections.rst
@@ -1150,6 +1150,8 @@ variants of :func:`functools.lru_cache`::
             return value
 
         def __setitem__(self, key, value):
+            if key in self:
+                self.move_to_end(key)
             super().__setitem__(key, value)
             if len(self) > self.maxsize:
                 oldest = next(iter(self))