def parse_GECKO(cls, agentString):
        """
        Attempt to parse the given User-Agent string as a Gecko-based browser's
        user-agent.
        """
        identifier = 'Gecko/'
        start = agentString.find(identifier)
        if start != -1:
            end = agentString.find(' ', start)
            if end == -1:
                end = None
            version = agentString[start + len(identifier):end]
            try:
                version = int(version)
            except __HOLE__:
                pass
            else:
                return cls(browsers.GECKO, (version,))
dataset/ETHPy150Open twisted/nevow/nevow/useragent.py/UserAgent.parse_GECKO