code: def test_sanitize_confounds(inputs, flag):
      """Should correctly catch inputs that are a single image."""
      _, singleflag = sanitize_confounds(inputs)
      assert singleflag is flag
  
imports: import pytest
  from nilearn.interfaces.fmriprep.load_confounds_utils import _get_file_name, sanitize_confounds
  from nilearn.interfaces.fmriprep.tests._testing import create_tmp_filepath
label_desc: Use image node_id 1 for calling a global function with example usage: test_sanitize_confounds(inputs, flag) without return types