code: def test_add_models_to_empty(self):
      elda = self.get_elda()
  
      ensemble = EnsembleLda(id2word=common_dictionary, num_models=0)
      ensemble.add_model(elda.ttda[0:1])
      ensemble.add_model(elda.ttda[1:])
      ensemble.recluster()
      np.testing.assert_allclose(
          ensemble.get_topics(), elda.get_topics(), rtol=RTOL
      )
  
      # persisting an ensemble that is entirely built from existing ttdas
      fname = get_tmpfile("gensim_models_ensemblelda")
      ensemble.save(fname)
      loaded_ensemble = EnsembleLda.load(fname)
      np.testing.assert_allclose(
          loaded_ensemble.get_topics(), elda.get_topics(), rtol=RTOL
      )
      self.test_inference(loaded_ensemble)
  
imports: import os
  import logging
  import unittest
  import numpy
  from copy import deepcopy
  import pytest
  from gensim.models import EnsembleLda, LdaMulticore, LdaModel
  from gensim.test.utils import datapath, get_tmpfile, common_corpus, common_dictionary
label_desc: Use image node_id 17 for calling the TestEnsembleLda obj's underlying member method code with example usage: obj.test_add_models_to_empty() without return types