Improve accuracy of sequence and mapping checks.
diff --git a/Misc/NEWS b/Misc/NEWS
index b1f2043..c51b74b 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -202,6 +202,9 @@
 Extension modules
 -----------------
 
+- operator.isMappingType() and operator.isSequenceType() now give
+  fewer false positives.
+
 - socket.sslerror is now a subclass of socket.error .  Also added
   socket.error to the socket module's C API.