--- random.txt	2009-10-07 01:22:26.000000000 -0400
+++ random.edit.txt	2009-11-02 15:26:17.000000000 -0500
@@ -41,6 +41,9 @@
 .. versionadded:: 2.4
    the :meth:`getrandbits` method.
 
+.. versionchanged:: 2.3
+   Substituted MersenneTwister for Wichmann-Hill.
+
 As an example of subclassing, the :mod:`random` module provides the
 :class:`WichmannHill` class that implements an alternative generator in pure
 Python.  The class provides a backward compatible way to reproduce results from
@@ -50,8 +53,11 @@
 known to fail some stringent randomness tests.  See the references below for a
 recent variant that repairs these flaws.
 
-.. versionchanged:: 2.3
-   Substituted MersenneTwister for Wichmann-Hill.
+The :mod:`random` module also provides the :class:`SystemRandom` class which
+uses the system function :func:`os.urandom`. Because of this, it should be
+unpredictable enough for cryptographic applications (although its exact quality
+depends on the OS implementation). However, it also means that the state cannot
+be saved or loaded and so the numbers returned aren't reproducible.
 
 Bookkeeping functions: