code: def get_board_mapping_parent_items(self, team_context, child_backlog_context_category_ref_name, workitem_ids):
          
          project = None
          team = None
          if team_context is not None:
              if team_context.project_id:
                  project = team_context.project_id
              else:
                  project = team_context.project
              if team_context.team_id:
                  team = team_context.team_id
              else:
                  team = team_context.team
  
          route_values = {}
          if project is not None:
              route_values['project'] = self._serialize.url('project', project, 'string')
          if team is not None:
              route_values['team'] = self._serialize.url('team', team, 'string')
          query_parameters = {}
          if child_backlog_context_category_ref_name is not None:
              query_parameters['childBacklogContextCategoryRefName'] = self._serialize.query('child_backlog_context_category_ref_name', child_backlog_context_category_ref_name, 'str')
          if workitem_ids is not None:
              workitem_ids = ",".join(map(str, workitem_ids))
              query_parameters['workitemIds'] = self._serialize.query('workitem_ids', workitem_ids, 'str')
          response = self._send(http_method='GET',
                                location_id='186abea3-5c35-432f-9e28-7a15b4312a0e',
                                version='5.0-preview.1',
                                route_values=route_values,
                                query_parameters=query_parameters)
          return self._deserialize('[ParentChildWIMap]', self._unwrap_collection(response))
docs: GetBoardMappingParentItems.
          [Preview API] Returns the list of parent field filter model for the given list of workitem ids
          :param :class:`<TeamContext> <azure.devops.v5_0.work.models.TeamContext>` team_context: The team context for the operation
          :param str child_backlog_context_category_ref_name:
          :param [int] workitem_ids:
          :rtype: [ParentChildWIMap]