code: def _get_random_imgs(shape, length):
      rng = _rng()
      return [Nifti1Image(rng.uniform(size=shape), np.eye(4))] * length
  
imports: import shutil
  from tempfile import mkdtemp
  import numpy
  import pytest
  from joblib import Memory
  from nibabel import Nifti1Image
  from numpy.testing import assert_array_equal
  from nilearn._utils.exceptions import DimensionError
  from nilearn._utils.testing import write_imgs_to_path
  from nilearn.conftest import _rng
  from nilearn.image import get_data
  from nilearn.maskers import MultiNiftiMasker
label_desc: Use image node_id 7 for calling a global function with example usage: _get_random_imgs(shape, length) and returns: unknown