class_docstr: Note: Tests currently do a poor job of testing functionality
code: def setup_class(self, tmpdir):
      # setup
      tmpdir.chdir()
      noise = np.fromfunction(self.fake_noise_fun, self.fake_data.shape)
      self.realigned_file = utils.save_toy_nii(
          self.fake_data + noise, self.filenames["functionalnii"]
      )
      mask = np.ones(self.fake_data.shape[:3])
      mask[0, 0, 0] = 0
      mask[0, 0, 1] = 0
      mask1 = utils.save_toy_nii(mask, self.filenames["masknii"])
  
      other_mask = np.ones(self.fake_data.shape[:3])
      other_mask[0, 1, 0] = 0
      other_mask[1, 1, 0] = 0
      mask2 = utils.save_toy_nii(other_mask, self.filenames["masknii2"])
  
      self.mask_files = [mask1, mask2]
  
imports: import os
  import nibabel
  import numpy
  import pytest
  from ...testing import utils
  from ..confounds import CompCor, TCompCor, ACompCor
label_desc: Use image node_id 1 for calling the TestCompCor obj's underlying member method code with example usage: obj.setup_class(tmpdir) without return types