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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 Instance(expected, message="Not an instance of {}"):
 """ Creates a validator that checks if the given value is an instance of ``expected``. A custom message can be specified with ``message``. """

    @wraps(Instance)
    def built(value):
        if not isinstance(value, expected):
            raise Error(message.format(expected.__name__))
        return value
    return built