code: def test_encoding(self):
      # UTF-8 with BOM
      ds = self._dataset(["utf8sig.txt"], encoding="utf-8-sig")
      assert ds[0] == "テスト1\n"
      assert ds[1] == "Test2\n"
      assert ds[2] == "Test3\n"
  
imports: from __future__ import unicode_literals
  import os
  import pickle
  import unittest
  import six
  from chainer import datasets
  from chainer import testing
label_desc: Use image node_id 14 for calling the TestTextDataset obj's underlying member method code with example usage: obj.test_encoding() without return types