add references between getopt and optparse docs
diff --git a/Doc/lib/libgetopt.tex b/Doc/lib/libgetopt.tex
index 558aafa..d8f1de7 100644
--- a/Doc/lib/libgetopt.tex
+++ b/Doc/lib/libgetopt.tex
@@ -143,3 +143,7 @@
 if __name__ == "__main__":
     main()
 \end{verbatim}
+
+\begin{seealso}
+  \seemodule{optparse}{More object-oriented command line option parsing}
+\end{seealso}