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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 _ParseOrMerge(self, lines, message):
 """Converts a text representation of a protocol message into a message. Args: lines: Lines of a message's text representation. message: A protocol buffer message to merge into. Raises: ParseError: On text parsing problems. """

    tokenizer = Tokenizer(lines)
    while not tokenizer.AtEnd():
      self._MergeField(tokenizer, message)