code: def _create_dummy_icdar_json(self, json_name):
      image_1 = {
          "id": 0,
          "width": 640,
          "height": 640,
          "file_name": "fake_name.jpg",
      }
      image_2 = {
          "id": 1,
          "width": 640,
          "height": 640,
          "file_name": "fake_name1.jpg",
      }
  
      annotation_1 = {
          "id": 1,
          "image_id": 0,
          "category_id": 0,
          "area": 400,
          "bbox": [50, 60, 20, 20],
          "iscrowd": 0,
          "segmentation": [[50, 60, 70, 60, 70, 80, 50, 80]],
      }
  
      annotation_2 = {
          "id": 2,
          "image_id": 0,
          "category_id": 0,
          "area": 900,
          "bbox": [100, 120, 30, 30],
          "iscrowd": 0,
          "segmentation": [[100, 120, 130, 120, 120, 150, 100, 150]],
      }
  
      annotation_3 = {
          "id": 3,
          "image_id": 0,
          "category_id": 0,
          "area": 1600,
          "bbox": [150, 160, 40, 40],
          "iscrowd": 1,
          "segmentation": [[150, 160, 190, 160, 190, 200, 150, 200]],
      }
  
      annotation_4 = {
          "id": 4,
          "image_id": 0,
          "category_id": 0,
          "area": 10000,
          "bbox": [250, 260, 100, 100],
          "iscrowd": 1,
          "segmentation": [[250, 260, 350, 260, 350, 360, 250, 360]],
      }
      annotation_5 = {
          "id": 5,
          "image_id": 1,
          "category_id": 0,
          "area": 10000,
          "bbox": [250, 260, 100, 100],
          "iscrowd": 1,
          "segmentation": [[250, 260, 350, 260, 350, 360, 250, 360]],
      }
      annotation_6 = {
          "id": 6,
          "image_id": 1,
          "category_id": 0,
          "area": 0,
          "bbox": [0, 0, 0, 0],
          "iscrowd": 1,
          "segmentation": [[250, 260, 350, 260, 350, 360, 250, 360]],
      }
      annotation_7 = {
          "id": 7,
          "image_id": 1,
          "category_id": 2,
          "area": 10000,
          "bbox": [250, 260, 100, 100],
          "iscrowd": 1,
          "segmentation": [[250, 260, 350, 260, 350, 360, 250, 360]],
      }
      annotation_8 = {
          "id": 8,
          "image_id": 1,
          "category_id": 0,
          "area": 10000,
          "bbox": [250, 260, 100, 100],
          "iscrowd": 1,
          "segmentation": [[250, 260, 350, 260, 350, 360, 250, 360]],
      }
  
      categories = [
          {
              "id": 0,
              "name": "text",
              "supercategory": "text",
          }
      ]
  
      fake_json = {
          "images": [image_1, image_2],
          "annotations": [
              annotation_1,
              annotation_2,
              annotation_3,
              annotation_4,
              annotation_5,
              annotation_6,
              annotation_7,
              annotation_8,
          ],
          "categories": categories,
      }
      self.metainfo = dict(classes=("text"))
      mmengine.dump(fake_json, json_name)
  
file_path: mmocr/tests/test_datasets/test_icdar_dataset.py
imports: import os.path
  import tempfile
  from unittest import TestCase
  import mmengine
  from mmocr.datasets.icdar_dataset import IcdarDataset
label_desc: Use image node_id 1 for calling the TestIcdarDataset obj's underlying member method code with example usage: obj._create_dummy_icdar_json(json_name) without return types