diff --git a/Doc/library/shelve.rst b/Doc/library/shelve.rst
index f7f7bf9..0650b41 100644
--- a/Doc/library/shelve.rst
+++ b/Doc/library/shelve.rst
@@ -27,14 +27,15 @@
 
    Because of Python semantics, a shelf cannot know when a mutable
    persistent-dictionary entry is modified.  By default modified objects are
-   written only when assigned to the shelf (see :ref:`shelve-example`).  If the
-   optional *writeback* parameter is set to *True*, all entries accessed are
-   cached in memory, and written back on :meth:`sync` and :meth:`close`; this
-   can make it handier to mutate mutable entries in the persistent dictionary,
-   but, if many entries are accessed, it can consume vast amounts of memory for
-   the cache, and it can make the close operation very slow since all accessed
-   entries are written back (there is no way to determine which accessed entries
-   are mutable, nor which ones were actually mutated).
+   written *only* when assigned to the shelf (see :ref:`shelve-example`).  If the
+   optional *writeback* parameter is set to *True*, all entries accessed are also
+   cached in memory, and written back on :meth:`~Shelf.sync` and
+   :meth:`~Shelf.close`; this can make it handier to mutate mutable entries in
+   the persistent dictionary, but, if many entries are accessed, it can consume
+   vast amounts of memory for the cache, and it can make the close operation
+   very slow since all accessed entries are written back (there is no way to
+   determine which accessed entries are mutable, nor which ones were actually
+   mutated).
 
    .. note::
 
diff --git a/Lib/shelve.py b/Lib/shelve.py
index 8271dfe..52e471a 100644
--- a/Lib/shelve.py
+++ b/Lib/shelve.py
@@ -136,11 +136,12 @@
             self.dict.close()
         except AttributeError:
             pass
-        # _ClosedDict can be None when close is called from __del__ during shutdown
-        if _ClosedDict is None:
-            self.dict = None
-        else:
+        # Catch errors that may happen when close is called from __del__
+        # because CPython is in interpreter shutdown.
+        try:
             self.dict = _ClosedDict()
+        except (NameError, TypeError):
+            self.dict = None
 
     def __del__(self):
         if not hasattr(self, 'writeback'):
diff --git a/Lib/test/test_shelve.py b/Lib/test/test_shelve.py
index 9699043..066208a 100644
--- a/Lib/test/test_shelve.py
+++ b/Lib/test/test_shelve.py
@@ -122,6 +122,19 @@
         self.assertEqual(len(d1), 1)
         self.assertEqual(len(d2), 1)
 
+    def test_writeback_also_writes_immediately(self):
+        # Issue 5754
+        d = {}
+        key = 'key'
+        encodedkey = key.encode('utf-8')
+        s = shelve.Shelf(d, writeback=True)
+        s[key] = [1]
+        p1 = d[encodedkey]  # Will give a KeyError if backing store not updated
+        s['key'].append(2)
+        s.close()
+        p2 = d[encodedkey]
+        self.assertNotEqual(p1, p2)  # Write creates new object in store
+
 
 from test import mapping_tests