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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 add(self, item, value):
 """Add an attribute value to our object instance. :param str item: Application attribute name :param any value: Value to associate with the attribute :raises: AttributeError """

        if item in self.__dict__[self.ATTRIBUTES].keys():
            raise AttributeError('%s already exists' % item)
        setattr(self, item, value)