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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def config_attributes(self):
 """ Helper method used by TorConfig when generating a torrc file. """


        rtn = [('HiddenServiceDir', str(self.dir))]
        if self.conf._supports['HiddenServiceDirGroupReadable'] \
           and self.group_readable:
            rtn.append(('HiddenServiceDirGroupReadable', str(1)))
        for port in self.ports:
            rtn.append(('HiddenServicePort', str(port)))
        if self.version:
            rtn.append(('HiddenServiceVersion', str(self.version)))
        for authline in self.authorize_client:
            rtn.append(('HiddenServiceAuthorizeClient', str(authline)))
        return rtn