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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 add_intf_router(self, rout_id, tenant_id, subnet_lst):
 """Add the interfaces to a router. """

        try:
            for subnet_id in subnet_lst:
                body = {'subnet_id': subnet_id}
                intf = self.neutronclient.add_interface_router(rout_id,
                                                               body=body)
                intf.get('port_id')
        except Exception as exc:
            LOG.error("Failed to create router intf ID %(id)s,"
                      " Exc %(exc)s", {'id': rout_id, 'exc': str(exc)})
            return False
        return True