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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 is_modified(self):
 """ Returns whether model is modified or not """

        if len(self.__modified_data__) or len(self.__deleted_fields__):
            return True

        for value in self.__original_data__.values():
            try:
                if value.is_modified():
                    return True
            except AttributeError:
                pass

        return False