finish task

def put(self, udid):
        ''' finish task '''
        data = tornado.escape.json_decode(self.request.body)
        id = data['id']
        result = data['result']
        if self.results.get(id) is None:
            self.results[id] = result
        else:
            that = self.results[id]
            that.write(json.dumps(result))
            that.finish()
            self.results.pop(id, None)
        self.write('Success')
        self.finish()