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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 save_controls(self, parameterstep: 'timetools.PeriodConstrArg' = None, simulationstep: 'timetools.PeriodConstrArg' = None, auxfiler: 'Optional[auxfiletools.Auxfiler]' = None):
 """Save the control parameters of the |Model| object handled by each |Element| object and eventually the ones handled by the given |Auxfiler| object."""

        if auxfiler:
            auxfiler.save(parameterstep, simulationstep)
        for element in printtools.progressbar(self):
            element.model.parameters.save_controls(
                parameterstep=parameterstep,
                simulationstep=simulationstep,
                auxfiler=auxfiler)