code: def test_save_and_load(self):
      char_vocab_size = 100
      word_vocab_size = 10000
      num_labels = 10
  
      model = BiLSTMCRF(
          char_vocab_size=char_vocab_size,
          word_vocab_size=word_vocab_size,
          num_labels=num_labels,
      )
      model, loss = model.build()
  
      self.assertFalse(os.path.exists(self.weights_file))
      self.assertFalse(os.path.exists(self.params_file))
  
      save_model(model, self.weights_file, self.params_file)
  
      self.assertTrue(os.path.exists(self.weights_file))
      self.assertTrue(os.path.exists(self.params_file))
  
      model = load_model(self.weights_file, self.params_file)
  
file_path: anago/tests/test_model.py
imports: import os
  import shutil
  import unittest
  from anago.models import BiLSTMCRF, load_model, save_model
label_desc: Use image node_id 4 for calling the TestModel obj's underlying member method code with example usage: obj.test_save_and_load() without return types