code: def test_save_text_format(self):
      corpus = WSCorpus()
      corpus.load(self.folder, "COLUMN")
      corpus.save(self.saved_ws_folder, "TEXT")
  
file_path: underthesea/tests/corpus/test_ws.py
imports: from os.path import dirname, join
  from unittest import TestCase
  from underthesea.corpus.ws_corpus import WSCorpus
label_desc: Use image node_id 3 for calling the TestWSCorpus obj's underlying member method code with example usage: obj.test_save_text_format() without return types