'Determine whether a line is a legal end of RFC 2822 headers.
You may override this method if your application wants to bend the
rules, e.g. to strip trailing whitespace, or to recognize MH template
separators (\'--------\').  For convenience (e.g. for code reading from
sockets) a line consisting of \r\n also matches.'

def islast(self, line):

    return (line in _blanklines)
