code: def test_dbcs(self):
      # cp949 decoder is simple with only 1 or 2 bytes sequences.
      decoder = codecs.getincrementaldecoder("cp949")()
      self.assertEqual(
          decoder.decode(b"\xc6\xc4\xc0\xcc\xbd"), "\ud30c\uc774"
      )
      self.assertEqual(
          decoder.decode(b"\xe3 \xb8\xb6\xc0\xbb"),
          "\uc36c \ub9c8\uc744",
      )
      self.assertEqual(decoder.decode(b""), "")
  
imports: import _multibytecodec
  import codecs
  import io
  import sys
  import textwrap
  import unittest
  from test import support
  from test.support import os_helper
  from test.support.os_helper import TESTFN
label_desc: Use image node_id 1 for calling the Test_IncrementalDecoder obj's underlying member method code with example usage: obj.test_dbcs() without return types