code: def get_hosting_device_resources(self, context, id, complementary_id,
                                       tenant_id, mgmt_nw_id):
          
          mgmt_port = None
          # Ports for hosting device may not yet have 'device_id' set to
          # Nova assigned uuid of VM instance. However, those ports will still
          # have 'device_owner' attribute set to complementary_id. Hence, we
          # use both attributes in the query to ensure we find all ports.
          query = context.session.query(models_v2.Port)
          query = query.filter(expr.or_(
              models_v2.Port.device_id == id,
              models_v2.Port.device_owner == complementary_id))
          for port in query:
              if port['network_id'] != mgmt_nw_id:
                  raise Exception
              else:
                  mgmt_port = port
          return {'mgmt_port': mgmt_port}
docs: Returns information about all resources for a hosting device.