code: def delete_network_all_subnets(self, net_id):
          
          try:
              body = {'network_id': net_id}
              subnet_list = self.neutronclient.list_subnets(body=body)
              subnet_list = subnet_list.get('subnets')
              for subnet in subnet_list:
                  if subnet.get('network_id') == net_id:
                      subnet_id = subnet.get('id')
                      self.neutronclient.delete_subnet(subnet_id)
          except Exception as exc:
              LOG.error("Failed to delete subnet for net %(net)s "
                        "Exc %(exc)s", {'net': net_id, 'exc': str(exc)})
              return False
          try:
              self.neutronclient.delete_network(net_id)
          except Exception as exc:
              LOG.error("Failed to delete network %(net)s Exc %(exc)s",
                        {'net': net_id, 'exc': str(exc)})
              return False
          return True
docs: Delete the openstack network including all its subnets.