Emphasize that Unpickler.memo is not necessarily a dict.
diff --git a/Doc/library/pickle.rst b/Doc/library/pickle.rst
index 0a958a7..6c2b269 100644
--- a/Doc/library/pickle.rst
+++ b/Doc/library/pickle.rst
@@ -334,8 +334,9 @@
.. attribute:: memo
- Dictionary holding previously unpickled objects to allow shared or
- recursive objects to unpickled by reference as opposed to by value.
+ Dictionary-like object holding previously unpickled objects to allow
+ shared or recursive objects to unpickled by reference as opposed to
+ by value.
.. _pickle-picklable: