code: def __init__(self, length):
      self.length = length
  
file_path: qlib/tests/rl/test_data_queue.py
imports: import multiprocessing
  import time
  import numpy
  import pandas
  from torch.utils.data import Dataset, DataLoader
  from qlib.rl.utils.data_queue import DataQueue
label_desc: Use image node_id 1 to create a new DummyDataset object from inherited base classes: Dataset with example: obj = DummyDataset(length)