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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 unregister_project_nodes(self, node):
 """ Unregisters given Node children. :param node: Node. :type node: ProjectNode or DirectoryNode """


        for node in reversed(list(foundations.walkers.nodes_walker(node))):
            if node.family == "Directory":
                self.unregister_directory(node)
            elif node.family == "File":
                self.unregister_file(node)