class_docstr: Random Dataset.
  
  This class is modified from RandomDataset in
  https://github.com/PyTorchLightning/pytorch-lightning/
  blob/master/pytorch_lightning/demos/boring_classes.py
  
  :param _type_ Dataset: _description_
code: def __init__(self, size: int, length: int):
      self.len = length
      self.data = torch.randn(length, 3, size, size)
  
file_path: BigDL/python/nano/example/pytorch/inference_optimizer/export_model/export_model.py
imports: import torch
  from torchvision.models import resnet50
  from bigdl.nano.pytorch import InferenceOptimizer
  from torch.utils.data import DataLoader, Dataset
label_desc: Use image node_id 1 to create a new RandomDataset object from inherited base classes: Dataset with example: obj = RandomDataset(size, length)