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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _insert_breaklines(self):
 """Inserts a breakline instead of a trailing space if the chunk is in CJK. """

    target_chunks = ChunkList()
    for chunk in self:
      if chunk.word[-1] == ' ' and chunk.has_cjk():
        chunk.word = chunk.word[:-1]
        target_chunks.append(chunk)
        target_chunks.append(chunk.breakline())
      else:
        target_chunks.append(chunk)
    self.list = target_chunks