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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 _getAvailableInstrumentsDisplayList(self):
 """ Returns a DisplayList with the available Instruments registered in Bika-Setup. Only active Instruments are fetched. Used to fill the Instruments MultiSelectionWidget """

        bsc = getToolByName(self, 'bika_setup_catalog')
        items = [(i.UID, i.Title)
                 for i in bsc(portal_type='Instrument',
                              is_active=True)]
        items.sort(lambda x, y: cmp(x[1], y[1]))
        return DisplayList(list(items))