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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 tokenize_sign(self, word):
 """This is for tokenizing cuneiform signs."""

        if self.language == 'akkadian':
            sign_tokens = tokenize_akkadian_signs(word)
        else:
            sign_tokens = 'Language must be written using cuneiform.'

        return sign_tokens