code: def setup_class(self, tmpdir_factory):
      tempdir = tmpdir_factory.mktemp("test")
      self.orig_dir = tempdir.chdir()
      utils.save_toy_nii(self.fake_fmri_data, self.filenames["in_file"])
      utils.save_toy_nii(
          self.fake_label_data, self.filenames["label_files"]
      )
  
file_path: nipype/nipype/interfaces/tests/test_nilearn.py
imports: import os
  import numpy
  from ...testing import utils
  from ..None import nilearn
  from ...pipeline import engine
  import pytest
  import numpy.testing
label_desc: Use image node_id 1 for calling the TestSignalExtraction obj's underlying member method code with example usage: obj.setup_class(tmpdir_factory) without return types