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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 classattribute(func):
 """Wrap a function as a class attribute. This differs from attribute by identifying attributes explicitly listed in a class definition rather than those only defined on instances of a class. """

    attr = abc.abstractmethod(func)
    attr.__iclassattribute__ = True
    attr = _property(attr)
    return attr