xxxxx.xxxxx.creative.delete
        ===================================
        删除一个创意

def delete(self, creative_id, nick=None):
        '''xxxxx.xxxxx.creative.delete
        ===================================
        删除一个创意'''
        request = TOPRequest('xxxxx.xxxxx.creative.delete')
        request['creative_id'] = creative_id
        if nick!=None: request['nick'] = nick
        self.create(self.execute(request), fields=['success','result','success','result_code','result_message'], models = {'result':Creative})
        return self.result