Fix issue3428 - Document HTTPMessage class.
diff --git a/Doc/library/httplib.rst b/Doc/library/httplib.rst
index f7d9328..7bd85a3 100644
--- a/Doc/library/httplib.rst
+++ b/Doc/library/httplib.rst
@@ -93,6 +93,14 @@
.. versionadded:: 2.0
+.. class:: HTTPMessage
+
+ An :class:`HTTPMessage` instance is used to hold the headers from an HTTP
+ response. It is implemented using the :class:`mimetools.Message` class and
+ provides utility functions to deal with HTTP Headers. It is not directly
+ instantiated by the users.
+
+
The following exceptions are raised as appropriate: