code: def __len__(self):
      return self.nSamples
  
imports: from PIL import Image
  import torch
  import torch.backends.cudnn
  import torch.utils.data
  import torch.nn.functional
  import torchvision.transforms
  import numpy
  from collections import OrderedDict
  import importlib
  from .utils import CTCLabelConverter
  import math
label_desc: Use image node_id 2 for calling the ListDataset obj's underlying member method code with example usage: obj.__len__() and returns: self