code: def test_empty_results(self):
      # create dummy data
      fake_json_file = osp.join(self.tmp_dir.name, "fake_data.json")
      self._create_dummy_lvis_json(fake_json_file)
      lvis_metric = LVISMetric(ann_file=fake_json_file, metric="bbox")
      lvis_metric.dataset_meta = dict(
          classes=["aerosol_can", "air_conditioner"]
      )
      bboxes = np.zeros((0, 4))
      labels = np.array([])
      scores = np.array([])
      dummy_mask = np.zeros((0, 10, 10), dtype=np.uint8)
      empty_pred = dict(
          bboxes=torch.from_numpy(bboxes),
          scores=torch.from_numpy(scores),
          labels=torch.from_numpy(labels),
          masks=torch.from_numpy(dummy_mask),
      )
      lvis_metric.process(
          {},
          [
              dict(
                  pred_instances=empty_pred,
                  img_id=0,
                  ori_shape=(640, 640),
              )
          ],
      )
      # lvis api Index error will be caught
      lvis_metric.evaluate(size=1)
  
imports: import os.path
  import tempfile
  import unittest
  import numpy
  import pycocotools.mask
  import torch
  from mmdet.evaluation.metrics import LVISMetric
  from mmengine.fileio import dump
label_desc: Use image node_id 11 for calling the TestLVISMetric obj's underlying member method code with example usage: obj.test_empty_results() without return types