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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 segment(self, line):
 """ Tokenizes single sentence and adds special BOS and EOS tokens. :param line: sentence returns: list representing tokenized sentence """

        line = line.strip().split()
        entry = [self.tok2idx[i] for i in line]
        entry = [config.BOS] + entry + [config.EOS]
        return entry