code: def __getitem__(self, index):
      item = {}
      item[self.image_key] = torch.randn(self.H, self.W, 3)
      item[self.txt_key] = f"This is meaningless fake text No.{index}"
      item[self.control_key] = torch.randn(self.H, self.W, 3)
      return item
  
file_path: NeMo/nemo/collections/multimodal/data/controlnet/controlnet_dataset.py
imports: import torch
  from nemo.collections.multimodal.data.common.webdataset import WebDatasetCommon
  from nemo.collections.multimodal.data.stable_diffusion.augmentation.augmentations import construct_image_augmentations, identical_transform
  from nemo.core.classes import Dataset
label_desc: Use image node_id 2 for calling the ControlNetSyntheticDataset obj's underlying member method code with example usage: obj.__getitem__(index) and returns: item