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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 collect_variables(self, selections) -> None: """Apply method |ChangeItem.collect_variables| of the base class |ChangeItem| and also apply method |ExchangeItem.insert_variables| of class |ExchangeItem| to collect the relevant base variables handled by the devices of the given |Selections| object. True True land_dill land_lahn_1 land_lahn_2 land_lahn_3 """

        super().collect_variables(selections)
        self.insert_variables(self.device2base, self.basespecs, selections)