Mark deprecated modules as such.
diff --git a/Doc/library/md5.rst b/Doc/library/md5.rst
index 4408372..0495ff5 100644
--- a/Doc/library/md5.rst
+++ b/Doc/library/md5.rst
@@ -4,6 +4,7 @@
 
 .. module:: md5
    :synopsis: RSA's MD5 message digest algorithm.
+   :deprecated:
 
 
 .. deprecated:: 2.5