Document objects that can be used with the ``with`` statement.
diff --git a/Doc/lib/libthread.tex b/Doc/lib/libthread.tex
index 4914948..9e0c202 100644
--- a/Doc/lib/libthread.tex
+++ b/Doc/lib/libthread.tex
@@ -100,6 +100,19 @@
some thread, \code{False} if not.
\end{methoddesc}
+In addition to these methods, lock objects can also be used via the
+\keyword{with} statement, e.g.:
+
+\begin{verbatim}
+from __future__ import with_statement
+import thread
+
+a_lock = thread.allocate_lock()
+
+with a_lock:
+ print "a_lock is locked while this executes"
+\end{verbatim}
+
\strong{Caveats:}
\begin{itemize}