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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 add_or_update(self, app_id):
        '''
        Add or update the category.
        '''
        logger.info('Collect info: user-{0}, uid-{1}'.format(self.userinfo.uid, app_id))
        MCollect.add_or_update(self.userinfo.uid, app_id)
        out_dic = {'success': True}
        return json.dump(out_dic, self)