code: def __getitem__(self, item):
      return self._data[item]
  
imports: from functools import reduce
  from numpy import dtype
  from fastNLP.envs.imports import _NEED_IMPORT_TORCH
label_desc: Use image node_id 3 for calling the TorchNormalDataset obj's underlying member method code with example usage: obj.__getitem__(item) and returns: self