def get_file(self, key):
        raise NotImplementedError('Method must be implemented by subclass')
Generator to iterate over all nodes from `node` and down whether
dataset/ETHPy150Open babble/babble/include/jython/Lib/mailbox.py/Mailbox.get_file--crossover with--dataset/ETHPy150Open kivy/kivy/kivy/uix/treeview.py/TreeView.iterate_all_nodes