code: def test_call(self):
      tmp_dir = tempfile.TemporaryDirectory()
      dict_file = osp.join(tmp_dir.name, "fake_chars.txt")
      create_dummy_dict_file(dict_file)
      dict_gen = Dictionary(
          dict_file=dict_file,
          with_start=False,
          with_end=False,
          with_padding=True,
          with_unknown=False,
      )
      data_samples = [TextRecogDataSample()]
      postprocessor = CTCPostProcessor(
          max_seq_len=None, dictionary=dict_gen
      )
  
      # test decode output to index
      dummy_output = torch.Tensor(
          [
              [
                  [1, 100, 3, 4, 5, 6, 7, 8],
                  [100, 2, 3, 4, 5, 6, 7, 8],
                  [1, 2, 100, 4, 5, 6, 7, 8],
                  [1, 2, 100, 4, 5, 6, 7, 8],
                  [100, 2, 3, 4, 5, 6, 7, 8],
                  [1, 2, 3, 100, 5, 6, 7, 8],
                  [100, 2, 3, 4, 5, 6, 7, 8],
                  [1, 2, 3, 100, 5, 6, 7, 8],
              ]
          ]
      )
      data_samples = postprocessor(dummy_output, data_samples)
      self.assertEqual(data_samples[0].pred_text.item, "1020303")
  
file_path: mmocr/tests/test_models/test_textrecog/test_postprocessors/test_ctc_postprocessor.py
imports: import os.path
  import tempfile
  from unittest import TestCase
  import torch
  from mmocr.models.common.dictionary import Dictionary
  from mmocr.models.textrecog.postprocessors.ctc_postprocessor import CTCPostProcessor
  from mmocr.structures import TextRecogDataSample
  from mmocr.testing import create_dummy_dict_file
label_desc: Use image node_id 2 for calling the TestCTCPostProcessor obj's underlying member method code with example usage: obj.test_call() without return types