code: def do_batch(self, b):
      return self.retain(self.create_batch(self.before_batch(b)), b)
  
imports: from __future__ import annotations
  from ..torch_basics import *
  from torch.utils.data.dataloader import _MultiProcessingDataLoaderIter, _SingleProcessDataLoaderIter, _DatasetKind
label_desc: Use image node_id 18 for calling the DataLoader obj's underlying member method code with example usage: obj.do_batch(b) and returns: self