\method{get()} and \method{setdefault()} was only added in Python
2.2.)
-Finally, \class{Message} instances have two public instance variables:
+Finally, \class{Message} instances have some public instance variables:
\begin{memberdesc}{headers}
A list containing the entire set of header lines, in the order in
be used to read the message content.
\end{memberdesc}
+\begin{memberdesc}{unixfrom}
+The \UNIX{} \samp{From~} line, if the message had one, or an empty
+string. This is needed to regenerate the message in some contexts,
+such as an \code{mbox}-style mailbox file.
+\end{memberdesc}
+
\subsection{AddressList Objects \label{addresslist-objects}}