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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 fill_dcnm_subnet_info(self, tenant_id, subnet, start, end, gateway, sec_gateway, direc):
 """Fills the DCNM subnet parameters. Function that fills the subnet parameters for a tenant required by DCNM. """

        serv_obj = self.get_service_obj(tenant_id)
        fw_dict = serv_obj.get_fw_dict()
        fw_id = fw_dict.get('fw_id')
        if direc == 'in':
            name = fw_id[0:4] + fw_const.IN_SERVICE_SUBNET + (
                fw_id[len(fw_id) - 4:])
        else:
            name = fw_id[0:4] + fw_const.OUT_SERVICE_SUBNET + (
                fw_id[len(fw_id) - 4:])
        subnet_dict = {'enable_dhcp': False,
                       'tenant_id': tenant_id,
                       'name': name,
                       'cidr': subnet + '/24',
                       'gateway_ip': gateway,
                       'secondary_gw': sec_gateway,
                       'ip_version': 4}
        subnet_dict['allocation_pools'] = [{'start': start, 'end': end}]
        # TODO(padkrish) Network ID and subnet ID are not filled.
        return subnet_dict