code: def _call_all_datasets_func(self, name, *args, **kwargs):
      for dataset in self.datasets:
          value = getattr(dataset, name)(*args, **kwargs)
          if value is not None:
              # TODO: Log a warning here
              return value
              # raise RuntimeError("Functions returning values can't be "
              #                    "called through MMFConcatDataset")
          if (
              hasattr(dataset, "get_single_call_funcs")
              and name in dataset.get_single_call_funcs()
          ):
              return
  
file_path: mmf/mmf/datasets/concat_dataset.py
imports: import functools
  import types
  from torch.utils.data import ConcatDataset
label_desc: Use image node_id 4 for calling the MMFConcatDataset obj's underlying member method code with example usage: obj._call_all_datasets_func(name) and returns: value