SMTP 'DATA' command -- sends message data to server.

def data(self, msg):
        """SMTP 'DATA' command -- sends message data to server. """

        (code, repl) = yield self.docmd(b"data")

        if code != 354:
            raise smtplib.SMTPDataError(code, repl)
        else:
            if isinstance(msg, str):
                msg = smtplib._fix_eols(msg).encode('ascii')
            q = smtplib._quote_periods(msg)
            if q[-2:] != CRLF:
                q = q + CRLF
            q = q + b"." + CRLF
            #self.send(q)
            yield self.send(q)
            (code, msg) = yield self.getreply()
            return (code, msg)