code: def test_merge_from_list(self):
      from sahi.utils.coco import merge_from_list
  
      # load coco files to be combined
      coco_path1 = "tests/data/coco_utils/terrain1_coco.json"
      coco_path2 = "tests/data/coco_utils/terrain2_coco.json"
      coco_path3 = "tests/data/coco_utils/terrain3_coco.json"
      coco_dict1 = load_json(coco_path1)
      self.assertEqual(len(coco_dict1["images"]), 1)
      self.assertEqual(len(coco_dict1["annotations"]), 7)
      self.assertEqual(len(coco_dict1["categories"]), 1)
  
      coco_dict2 = load_json(coco_path2)
      self.assertEqual(len(coco_dict2["images"]), 1)
      self.assertEqual(len(coco_dict2["annotations"]), 5)
      self.assertEqual(len(coco_dict2["categories"]), 1)
  
      coco_dict3 = load_json(coco_path3)
      self.assertEqual(len(coco_dict3["images"]), 1)
      self.assertEqual(len(coco_dict3["annotations"]), 10)
      self.assertEqual(len(coco_dict3["categories"]), 1)
  
      # merge without desired_name2id
      merged_coco_dict = merge_from_list(
          [coco_dict1, coco_dict2, coco_dict3]
      )
      self.assertEqual(len(merged_coco_dict["images"]), 3)
      self.assertEqual(len(merged_coco_dict["annotations"]), 22)
      self.assertEqual(len(merged_coco_dict["categories"]), 2)
      self.assertEqual(
          merged_coco_dict["annotations"][12]["bbox"],
          coco_dict3["annotations"][0]["bbox"],
      )
      self.assertEqual(
          merged_coco_dict["annotations"][12]["id"],
          15,
      )
      self.assertEqual(
          merged_coco_dict["annotations"][12]["image_id"],
          5,
      )
      self.assertEqual(
          merged_coco_dict["annotations"][9]["category_id"],
          1,
      )
      self.assertEqual(
          merged_coco_dict["annotations"][9]["image_id"],
          3,
      )
  
imports: import os
  import shutil
  import unittest
  from sahi.utils.coco import merge, update_categories
  from sahi.utils.file import load_json
label_desc: Use image node_id 14 for calling the TestCocoUtils obj's underlying member method code with example usage: obj.test_merge_from_list() without return types