Tries to guess a sound logging configuration.

def auto(cls, syslog=None, stderr=None, level=None, extended=None,
             server=None):
        """Tries to guess a sound logging configuration.
        """
        level = norm_level(level) or logging.INFO
        if syslog is None and stderr is None:
            if sys.stderr.isatty() or syslog_path() is None:
                log.info('Defaulting to STDERR logging.')
                syslog, stderr = None, level
                if extended is None:
                    extended = (stderr or 0) <= logging.DEBUG
            else:
                log.info('Defaulting to logging with Syslog.')
                syslog, stderr = level, None
        return cls(syslog=syslog, stderr=stderr, extended=extended,
                   server=server)