docs: def set_simulation_duration(self, simulation_duration):
          """
          set the simulation_duration
          see: http://www.gsshawiki.com/Project_File:Required_Inputs
          """
          self.project_manager.setCard('TOT_TIME', str(simulation_duration.total_seconds()/60.0))
          super(EventMode, self).set_simulation_duration(simulation_duration)
          self.simulation_duration = simulation_duration