code: def create_os_dummy_rtr(self, tenant_id, fw_dict, is_fw_virt=False):
          
          res = fw_const.OS_DUMMY_RTR_CREATE_SUCCESS
          tenant_name = fw_dict.get('tenant_name')
          try:
              rtr_id = fw_dict.get('router_id')
              if rtr_id is None:
                  LOG.error("Invalid router id, attaching dummy interface"
                            " failed")
                  return False
              if is_fw_virt:
                  net_id = subnet_id = None
              else:
                  net_id, subnet_id = (
                      self._attach_dummy_intf_rtr(tenant_id, tenant_name,
                                                  rtr_id))
                  if net_id is None or subnet_id is None:
                      LOG.error("Invalid net_id or subnet_id, creating dummy"
                                " interface failed")
                      return False
          except Exception as exc:
              # Function _attach_dummy_intf_rtr already took care of
              # cleanup for error cases.
              LOG.error("Creation of Openstack Router failed "
                        "tenant %(tenant)s, Exception %(exc)s",
                        {'tenant': tenant_id, 'exc': str(exc)})
              res = fw_const.OS_DUMMY_RTR_CREATE_FAIL
          self.store_fw_db_router(tenant_id, net_id, subnet_id, rtr_id, res)
          return True
docs: Create the dummy interface and attach it to router.
  
          Attach the dummy interface to the Openstack router and store the
          info in DB.