code: def test_image_processor_to_json_string(self):
      image_processor = self.image_processing_class(
          **self.image_processor_dict
      )
      obj = json.loads(image_processor.to_json_string())
      for key, value in self.image_processor_dict.items():
          if key == "clusters":
              self.assertTrue(np.array_equal(value, obj[key]))
          else:
              self.assertEqual(obj[key], value)
  
imports: import json
  import os
  import tempfile
  import unittest
  import numpy
  from datasets import load_dataset
  from transformers.testing_utils import require_torch, require_vision, slow
  from transformers.utils import is_torch_available, is_vision_available
  from ...test_image_processing_common import ImageProcessingTestMixin, prepare_image_inputs
label_desc: Use image node_id 5 for calling the ImageGPTImageProcessingTest obj's underlying member method code with example usage: obj.test_image_processor_to_json_string() without return types