Return the entire message flatten as a string. When optional
\var{unixfrom} is \code{True}, the envelope header is included in the
returned string. \var{unixfrom} defaults to \code{False}.
+
+Note that this method is provided as a convenience and may not always
+format the message the way you want. For more flexibility,
+instantiate a \class{Generator} instance and use its
+\method{flatten()} method directly. For example:
+
+\begin{verbatim}
+from cStringIO import StringIO
+from email.Generator import Generator
+fp = StringIO()
+g = Generator(mangle_from_=False, maxheaderlen=60)
+g.flatten(msg)
+text = fp.getvalue()
+\end{verbatim}
\end{methoddesc}
\begin{methoddesc}[Message]{__str__}{}