code: def test_punkt_debug_decisions_custom_end(self):
      # Test debug_decisions on a text with two sentences,
      # split by a custom end character, based on Issue #2519
      class ExtLangVars(punkt.PunktLanguageVars):
          sent_end_chars = (".", "?", "!", "^")
  
      self.punkt_debug_decisions(
          "Subject: Some subject^ Attachments: Some attachments",
          n_sents=2,
          n_splits=1,
          lang_vars=ExtLangVars(),
      )
  
imports: from typing import List, Tuple
  import pytest
  from nltk.tokenize import LegalitySyllableTokenizer, StanfordSegmenter, SyllableTokenizer, TreebankWordTokenizer, TweetTokenizer, punkt, sent_tokenize, word_tokenize
  from nltk.tokenize.simple import CharTokenizer
label_desc: Use image node_id 21 for calling the TestTokenize obj's underlying member method code with example usage: obj.test_punkt_debug_decisions_custom_end() without return types