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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 attribute_exists(self, name):
 """ Returns if given attribute exists in the node. Usage:: True False :param name: Attribute name. :type name: unicode :return: Attribute exists. :rtype: bool """


        if name in self:
            if issubclass(self[name].__class__, Attribute):
                return True
        return False