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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 BatchLabelVocabulary(self):
 """Return all batch labels as a display list """

        bsc = getToolByName(self, 'bika_setup_catalog')
        ret = []
        for p in bsc(portal_type='BatchLabel',
                     is_active=True,
                     sort_on='sortable_title'):
            ret.append((p.UID, p.Title))
        return DisplayList(ret)