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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 _set_mtu_to_nics(self, conf):
 """ For all the nics of all the domains in the conf that have MTU set, save the MTU on the NIC definition. Args: conf (dict):
 Configuration spec to extract the domains from Returns: None """

        for dom_name, dom_spec in conf.get('domains', {}).items():
            for idx, nic in enumerate(dom_spec.get('nics', [])):
                net = self._get_net(conf, dom_name, nic)
                mtu = net.get('mtu', 1500)
                if mtu != 1500:
                    nic['mtu'] = mtu