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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 hide_restricted(self, ):
 """Hide the restricted buttons :returns: None :rtype: None :raises: None """

        tohide = [((self.reftrack.unload, self.unload_tb),
                   (self.reftrack.load, self.load_tb)),
                  ((self.reftrack.import_file, self.importtf_tb),
                   (self.reftrack.import_reference, self.importref_tb))]
        for (action1, btn1), (action2, btn2) in tohide:
            res1 = self.reftrack.is_restricted(action1)
            res2 = self.reftrack.is_restricted(action2)
            if res1 != res2:
                btn1.setEnabled(True)
                btn1.setHidden(res1)
                btn2.setHidden(res2)
            else:  # both are restricted, then show one but disable it
                btn1.setDisabled(True)
                btn1.setVisible(True)
                btn2.setVisible(False)