def parse_MSIE(cls, agentString):
        """
        Attempt to parse an Internet Explorer user-agent.
        """
        oldPrefix = 'Mozilla/4.0 (compatible; MSIE '
        newPrefix = 'Mozilla/5.0 (compatible; MSIE '
        for prefix in oldPrefix, newPrefix:
            if agentString.startswith(prefix):
                end = agentString.find(';', len(prefix))
                if end == -1:
                    end = None
                version = agentString[len(prefix):end]
                try:
                    version = map(int, version.split('.'))
                except __HOLE__:
                    pass
                else:
                    return cls(browsers.INTERNET_EXPLORER, tuple(version))
dataset/ETHPy150Open twisted/nevow/nevow/useragent.py/UserAgent.parse_MSIE