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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 selection_notification(self, model, property, info):
 """If a single state is selected, open the corresponding tab"""

        if model is not self.current_state_machine_m or len(self.current_state_machine_m.ongoing_complex_actions) > 0:
            return
        state_machine_m = model
        assert isinstance(state_machine_m.selection, Selection)
        if len(state_machine_m.selection.states) == 1 and len(state_machine_m.selection) == 1:
            self.activate_state_tab(state_machine_m.selection.get_selected_state())