code: def test_textset_convertion(self):
      local_set = LocalTextSet(self.texts, self.labels)
      local1 = local_set.to_local()
      distributed1 = local_set.to_distributed(self.sc)
      assert local1.is_local()
      assert distributed1.is_distributed()
      assert local1.get_texts() == distributed1.get_texts().collect()
  
      texts_rdd = self.sc.parallelize(self.texts)
      labels_rdd = self.sc.parallelize(self.labels)
      distributed_set = DistributedTextSet(texts_rdd, labels_rdd)
      local2 = distributed_set.to_local()
      distributed2 = distributed_set.to_distributed()
      assert local2.is_local()
      assert distributed2.is_distributed()
      assert local2.get_texts() == distributed2.get_texts().collect()
  
imports: import pytest
  import shutil
  from bigdl.optim.optimizer import SGD
  from zoo.feature.common import ChainedPreprocessing, Relations
  from zoo.feature.text import *
  from zoo.common.nncontext import *
  from zoo.models.textclassification import TextClassifier
  from zoo.models.textmatching import KNRM
  from zoo.pipeline.api.keras.models import Sequential
  from zoo.pipeline.api.keras.layers import TimeDistributed
  from zoo.pipeline.api.keras.objectives import SparseCategoricalCrossEntropy
label_desc: Use image node_id 4 for calling the TestTextSet obj's underlying member method code with example usage: obj.test_textset_convertion() without return types