def get_icon ( self, is_expanded ):
        if self.adaptee.is_file:
            return '<item>'

        if is_expanded:
            return '<open>'

        return '<open>'
Set a header for this response to a given value.
dataset/ETHPy150Open enthought/traitsui/examples/demo/Advanced/Adapted_tree_editor_demo.py/FileAdapter.get_icon--crossover with--dataset/ETHPy150Open falconry/falcon/falcon/response.py/Response.set_header