code: def test_InsertPunctuationChars(self) -> None:
      aug_punc_text = txtaugs.InsertPunctuationChars("all", 1.0, False)(
          self.texts, metadata=self.metadata
      )
  
      # Separator inserted between every character (including spaces/punctuation).
      self.assertEqual(
          aug_punc_text,
          [
              "T?h?e? ?q?u?i?c?k? ?b?r?o?w?n? ?'?f?o?x?'? ?c?o?u?l?d?n?'?t? "
              "?j?u?m?p? ?o?v?e?r? ?t?h?e? ?g?r?e?e?n?,? ?g?r?a?s?s?y? ?h?i?l?l?."
          ],
      )
      self.assertTrue(
          are_equal_metadata(
              self.metadata,
              self.expected_metadata["insert_punctuation_chars"],
          ),
      )
  
imports: import json
  import os
  import random
  import unittest
  from typing import Any, Dict, List
  from augly import text
  from augly.utils import TEXT_METADATA_PATH
label_desc: Use image node_id 9 for calling the TransformsTextUnitTest obj's underlying member method code with example usage: obj.test_InsertPunctuationChars() without return types