code: def test_empty(self):
      texts = ["", None]
  
      augs = [
          nac.OcrAug(),
          nac.KeyboardAug(),
      ]
  
      for text in texts:
          for aug in augs:
              augmented_data = aug.augment(text)
              self.assertEqual(len(augmented_data), 0)
  
file_path: nlpaug/test/augmenter/char/test_char.py
imports: import unittest
  import nlpaug.augmenter.char
  import nlpaug.util.text.tokenizer
  from nlpaug.util import Action
label_desc: Use image node_id 1 for calling the TestCharacter obj's underlying member method code with example usage: obj.test_empty() without return types