code: def wrap_dataloader(dl):
      dl = OneHot(dl, index=1, nclasses=10)
      dl = TypeCast(dl, index=0, dtype=np.float32)
      dl = BGRMeanSubtract(dl, index=0)
      return dl
  
file_path: neon/examples/cifar10_msra/data.py
imports: import numpy
  import os
  from tqdm import tqdm
  from neon.data import CIFAR10
  from neon.data.aeon_shim import AeonDataLoader
  from neon.data.dataloader_transformers import OneHot, TypeCast, BGRMeanSubtract
  from neon.util.persist import get_data_cache_or_nothing
  from PIL import Image
label_desc: Use image node_id 3 for calling a global function with example usage: wrap_dataloader(dl) and returns: dl