code: def maybe_download_sbs():
      """Download the SBS dataset to its expected location if necessary"""
      files = []
      for channel in 1, 2:
          idx = 1
          for row in "ABCDEFGH":
              for col in range(1, 13):
                  files.append(
                      "Channel%d-%02d-%s-%02d.tif"
                      % (channel, idx, row, col)
                  )
                  idx += 1
  
      path = maybe_download_example_images(["ExampleSBSImages"], files)
      #
      # Create the matlab files
      #
      import scipy.io.matlab.mio
  
      for filename in ["Channel1ILLUM.mat", "Channel2ILLUM.mat"]:
          pixels = np.ones((20, 30))
          scipy.io.matlab.mio.savemat(
              os.path.join(path, filename),
              {"Image": pixels},
              format="5",
          )
      return path
  
imports: import logging
  import base64
  import hashlib
  import numpy
  import os
  import unittest
  import tempfile
  import functools
  import scipy.io.matlab.mio
  import numpy
  import skimage.io
  from urllib.request import URLopener
  import cellprofiler_core.utilities.legacy
  from cellprofiler_core.pipeline import ImageFile
  import tests.frontend
label_desc: Use image node_id 11 for calling a global function with example usage: maybe_download_sbs() and returns: path