code: def test_process_from_file(self):
      dataset_names = ["pku", "cityu", "as", "msra"]
      for dataset_name in dataset_names:
          data_bundle = CWSPipe(
              dataset_name=dataset_name
          ).process_from_file()
          print(data_bundle)
  
file_path: fastNLP/tests/io/pipe/test_cws.py
imports: import pytest
  import os
  from fastNLP.io.pipe.cws import CWSPipe
label_desc: Use image node_id 1 for calling the TestCWSPipe obj's underlying member method code with example usage: obj.test_process_from_file() without return types