Remove use of the avant package; Helvetica isn't as pretty, but works for
acroread. The problem this solves is likely dependent on font availability,
so keeping things simple is a good solution.
diff --git a/Doc/texinputs/pypaper.sty b/Doc/texinputs/pypaper.sty
index 41b2572..3959637 100644
--- a/Doc/texinputs/pypaper.sty
+++ b/Doc/texinputs/pypaper.sty
@@ -16,4 +16,3 @@
% package.
%
\RequirePackage{times}\typeout{Using Times instead of Computer Modern.}
-\RequirePackage{avant}\typeout{Using AvantGarde instead of Helvetica.}