code: def __iter__(self):
      for input, _label in self.test_data:
          yield input
  
imports: from abc import ABC, abstractmethod
  from dataclasses import dataclass
  from typing import Generator, Optional, Tuple
  import pandas
  from gluonts.dataset import Dataset, DataEntry
  from gluonts.dataset.field_names import FieldName
label_desc: Use image node_id 2 for calling the InputDataset obj's underlying member method code with example usage: obj.__iter__() without return types