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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_xml_to_node(self, node):
 """ For exporting, set data on etree.Element `node`. """

        super(XBlock, self).add_xml_to_node(node)
        # Add children for each of our children.
        self.add_children_to_node(node)