code: def _load_line(self, image_path):
      if image_path is None:
          return None
  
      if not os.path.exists(image_path):
          if self.params.non_existing_as_empty:
              return np.zeros((1, 1), dtype=np.uint8)
          else:
              raise Exception(
                  "Image file at '{}' does not exist".format(image_path)
              )
  
      try:
          img = self._load_image(image_path)
      except:
          return None
  
      return img
  
imports: import codecs
  import os
  from copy import deepcopy
  from dataclasses import dataclass, field
  from typing import List
  import numpy
  import logging
  from paiargparse import pai_dataclass, pai_meta
  from tfaip.data.pipeline.definitions import PipelineMode, INPUT_PROCESSOR
  from calamari_ocr.ocr.dataset.datareader.base import CalamariDataGenerator, CalamariDataGeneratorParams, InputSample, SampleMeta
  from calamari_ocr.utils import split_all_ext, glob_all, keep_files_with_same_file_name
label_desc: Use image node_id 4 for calling the FileDataGenerator obj's underlying member method code with example usage: obj._load_line(image_path) and returns: img, None, np, None