code: def test_get_imageid2annotationlist_mapping(self):
      from sahi.utils.coco import get_imageid2annotationlist_mapping
  
      coco_path = "tests/data/coco_utils/combined_coco.json"
      coco_dict = load_json(coco_path)
      imageid2annotationlist_mapping = (
          get_imageid2annotationlist_mapping(coco_dict)
      )
      self.assertEqual(len(imageid2annotationlist_mapping), 2)
  
      def check_image_id(image_id):
          image_ids = [
              annotationlist["image_id"]
              for annotationlist in imageid2annotationlist_mapping[
                  image_id
              ]
          ]
          self.assertEqual(image_ids, [image_id] * len(image_ids))
  
      check_image_id(image_id=1)
      check_image_id(image_id=2)
  
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 12 for calling the TestCocoUtils obj's underlying member method code with example usage: obj.test_get_imageid2annotationlist_mapping() without return types