code: def test_is_word(self):
      self.assertTrue(not swap_ins.is_word("飞机"))
      self.assertTrue(swap_ins.is_word("看书"))
      self.assertTrue(swap_ins.is_word("人人"))
      self.assertTrue(not swap_ins.is_word("汽车"))
  
file_path: textflint/test/generation/transformation/CWS/test_cn_mlm.py
imports: import unittest
  from textflint.generation.transformation.CWS.cn_mlm import CnMLM
  from textflint.input.component.sample.cws_sample import CWSSample
label_desc: Use image node_id 2 for calling the TestCnMLM obj's underlying member method code with example usage: obj.test_is_word() without return types