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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 process_tokendef(cls, name, tokendefs=None):
 """Preprocess a dictionary of token definitions."""

        processed = cls._all_tokens[name] = {}
        tokendefs = tokendefs or cls.tokens[name]
        for state in list(tokendefs):
            cls._process_state(tokendefs, processed, state)
        return processed