Modified version of ../texinputs/pypaper.sty that specifies A4 paper.
diff --git a/Doc/paper-a4/pypaper.sty b/Doc/paper-a4/pypaper.sty
new file mode 100644
index 0000000..10b22f8
--- /dev/null
+++ b/Doc/paper-a4/pypaper.sty
@@ -0,0 +1,5 @@
+%
+%  Change this to say a4paper instead of letterpaper if you want A4.
+%
+\newcommand{\py@paper}{a4paper}
+\newcommand{\py@ptsize}{10pt}