code: def test_large_mmap_compressed(self):
      fname = get_tmpfile("gensim_models_lda.tst.gz")
      model = self.model
  
      # simulate storing large arrays separately
      model.save(fname, sep_limit=0)
  
      # test loading the large model arrays with mmap
      self.assertRaises(IOError, self.class_.load, fname, mmap="r")
  
imports: import logging
  import numbers
  import os
  import unittest
  import copy
  import numpy
  from numpy.testing import assert_allclose
  from gensim.corpora import mmcorpus, Dictionary
  from gensim.models import ldamodel, ldamulticore
  from gensim import matutils, utils
  from gensim.test import basetmtests
  from gensim.test.utils import datapath, get_tmpfile, common_texts
label_desc: Use image node_id 18 for calling the TestLdaModel obj's underlying member method code with example usage: obj.test_large_mmap_compressed() without return types