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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 getAnalysisServicesDisplayList(self):
        ''' Returns a Display List with the active Analysis Services
            available. The value is the keyword and the title is the
            text to be displayed.
        '''
        bsc = getToolByName(self, 'bika_setup_catalog')
        items = [('', '')] + [(o.getObject().Keyword, o.Title) for o in
                                bsc(portal_type = 'AnalysisService',
                                    is_active = True)]
        items.sort(lambda x, y: cmp(x[1].lower(), y[1].lower()))
        return DisplayList(list(items))