code: def group_data():
      
  
      tr_obj = np.load("%s/ref_id.npz" %direc_ref)['arr_0']
      groups = np.random.randint(0, 8, size=len(tr_obj))
      np.savez("ref_groups.npz", groups)
docs: Load the reference data, and assign each object
      a random integer from 0 to 7. Save the IDs.