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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 update_chars(self):
 """Update the current charters in the tokenizer."""

        # NOTE: We spoof non-Unix files by returning '\n' on StopIteration
        self.prior_char, self.char = self.char, next(self.characters, '\n')
        self.idx += 1