Re-apply patch #1700288 (first applied in r59931, rolled back in r59940)
now that ctypes uses a more supported method to create types:

Method cache optimization, by Armin Rigo, ported to 2.6 by Kevin Jacobs.
diff --git a/Objects/object.c b/Objects/object.c
index 788e732..dbe5658 100644
--- a/Objects/object.c
+++ b/Objects/object.c
@@ -1287,6 +1287,7 @@
 			goto done;
 	}
 
+#if 0 /* XXX this is not quite _PyType_Lookup anymore */
 	/* Inline _PyType_Lookup */
 	{
 		Py_ssize_t i, n;
@@ -1311,6 +1312,9 @@
 				break;
 		}
 	}
+#else
+	descr = _PyType_Lookup(tp, name);
+#endif
 
 	Py_XINCREF(descr);