javascript - 我有这个错误：无法读取未定义的属性“原型”

Question

我有这个错误：

Cannot read property 'prototype' of undefined

我使用 ccxt 和 express。我认为它表达了问题，但我不知道该怎么做。

'use strict';
import { response } from 'express';

const api = () => {
const ccxt = require ('ccxt');
let sum = 0;
let i = 0;
const express = require('express')

const app = express()

// Defining CORS
app.use(function(req, res, next) {
    res.setHeader(
      "Access-Control-Allow-Headers",
      "X-Requested-With,content-type"
    );
    res.setHeader("Access-Control-Allow-Origin", "*");
    res.setHeader(
      "Access-Control-Allow-Methods",
      "GET, POST, OPTIONS, PUT, PATCH, DELETE"
    );
    res.setHeader("Access-Control-Allow-Credentials", true);
    next();
});

...