code: def setUp(self):
      self.mnist_root = download.get_dataset_directory(
          os.path.join("pfnet", "chainer", "mnist")
      )
      self.kuzushiji_mnist_root = download.get_dataset_directory(
          os.path.join("pfnet", "chainer", "kuzushiji_mnist")
      )
      self.fashion_mnist_root = download.get_dataset_directory(
          os.path.join("pfnet", "chainer", "fashion-mnist")
      )
  
imports: import importlib
  import os
  import unittest
  import mock
  import numpy
  from chainer.dataset import download
  from chainer.datasets import get_fashion_mnist
  from chainer.datasets import get_fashion_mnist_labels
  from chainer.datasets import get_kuzushiji_mnist
  from chainer.datasets import get_kuzushiji_mnist_labels
  from chainer.datasets import get_mnist
  from chainer.datasets import tuple_dataset
  from chainer import testing
  from chainer.testing import attr
label_desc: Use image node_id 1 for calling the TestMnist obj's underlying member method code with example usage: obj.setUp() without return types