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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 remove_rtr_nwk_next_hop(self, rout_id, next_hop, subnet_lst, excl_list):
 """Remove the next hop for all networks of a tenant. """

        namespace = self.find_rtr_namespace(rout_id)
        if namespace is None:
            LOG.error("Unable to find namespace for router %s", rout_id)
            return False

        args = ['ip', 'route']
        ret = self.program_rtr_return(args, rout_id, namespace=namespace)
        if ret is None:
            LOG.error("Get routes return None %s", rout_id)
            return False
        routes = ret.split('\n')
        concat_lst = subnet_lst + excl_list
        for rout in routes:
            if len(rout) == 0:
                continue
            nwk = rout.split()[0]
            if nwk == 'default':
                continue
            nwk_no_mask = nwk.split('/')[0]
            if nwk_no_mask not in concat_lst and nwk not in concat_lst:
                args = ['route', 'del', '-net', nwk, 'gw', next_hop]
                ret = self.program_rtr(args, rout_id, namespace=namespace)
                if not ret:
                    LOG.error("Program router returned error for %s",
                              rout_id)
                    return False
        return True