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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 validate_key(self, key):
 """ Django normally warns about maximum key length, but we error on it. """

        if len(key) > 250:
            raise ValueError(
                "Cache key is longer than the maxmimum 250 characters: {}"
                .format(key),
            )
        return super(MySQLCache, self).validate_key(key)