Consistency:  In two \section{} headers, change {\tt ...} to \sectcode{...}.
diff --git a/Doc/ext.tex b/Doc/ext.tex
index 71343a5..596dd92 100644
--- a/Doc/ext.tex
+++ b/Doc/ext.tex
@@ -544,7 +544,7 @@
 be checked.
 
 
-\section{Format Strings for {\tt PyArg_ParseTuple()}}
+\section{Format Strings for \sectcode{PyArg_ParseTuple()}}
 
 The \code{PyArg_ParseTuple()} function is declared as follows:
 
@@ -738,7 +738,7 @@
     }
 \end{verbatim}
 %
-\section{The {\tt Py_BuildValue()} Function}
+\section{The \sectcode{Py_BuildValue()} Function}
 
 This function is the counterpart to \code{PyArg_ParseTuple()}.  It is
 declared as follows: