* Add clearer comment to initialization code.
* Add optional argument to popitem() -- modeled
  after Anthon van der Neut's C version.
* Fix method markup in docs.
diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py
index f232df4..9e984ba 100644
--- a/Lib/test/test_collections.py
+++ b/Lib/test/test_collections.py
@@ -768,12 +768,19 @@
 class GeneralMappingTests(mapping_tests.BasicTestMappingProtocol):
     type2test = OrderedDict
 
+    def test_popitem(self):
+        d = self._empty_mapping()
+        self.assertRaises(KeyError, d.popitem)
+
 class MyOrderedDict(OrderedDict):
     pass
 
 class SubclassMappingTests(mapping_tests.BasicTestMappingProtocol):
     type2test = MyOrderedDict
 
+    def test_popitem(self):
+        d = self._empty_mapping()
+        self.assertRaises(KeyError, d.popitem)
 
 import doctest, collections