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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_smart(self, value):
 """Set group is_smart property to value. Args: value: Boolean. """

        self.set_bool("is_smart", value)
        if value is True:
            if self.find("criteria") is None:
                # pylint: disable=attribute-defined-outside-init
                self.criteria = ElementTree.SubElement(self, "criteria")