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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 _get_selected_ids(self):
 """List of currently selected ids"""

        selection = self.get_selection()
        if selection.get_mode() != gtk.SELECTION_MULTIPLE:
            raise AttributeError('selected_ids only valid for select_multiple')
        model, selected_paths = selection.get_selected_rows()
        if selected_paths:
            return zip(*selected_paths)[0]
        else:
            return ()