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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 rate_limit(limit: int, key=None):
 """ Decorator for configuring rate limit and key in different functions. :param limit: :param key: :return: """


    def decorator(func):
        setattr(func, 'throttling_rate_limit', limit)
        if key:
            setattr(func, 'throttling_key', key)
        return func

    return decorator