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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 _find_chain_name(self, mac):
 """Find a rule associated with a given mac."""


        ipt_cmd = ['iptables', '-t', 'filter', '-S']
        cmdo = dsl.execute(ipt_cmd, root_helper=self._root_helper,
                           log_output=False)
        for o in cmdo.split('\n'):
            if mac in o.lower():
                chain = o.split()[1]
                LOG.info('Find %(chain)s for %(mac)s.',
                         {'chain': chain, 'mac': mac})
                return chain