D:\ethereum\Dkfuwq>node app.js
node:internal/modules/cjs/loader:936
  throw err;
  ^

Error: Cannot find module 'safe-buffer'
Require stack:
- D:\ethereum\Dkfuwq\node_modules\Koa\node_modules\content-disposition\index.js
- D:\ethereum\Dkfuwq\node_modules\Koa\lib\response.js
- D:\ethereum\Dkfuwq\node_modules\Koa\lib\application.js
- D:\ethereum\Dkfuwq\app.js
    at Function.Module._resolveFilename (node:internal/modules/cjs/loader:933:15)
    at Function.Module._load (node:internal/modules/cjs/loader:778:27)
    at Module.require (node:internal/modules/cjs/loader:1005:19)
    at require (node:internal/modules/cjs/helpers:102:18)
    at Object.<anonymous> (D:\ethereum\Dkfuwq\node_modules\Koa\node_modules\content-disposition\index.js:23:14)
    at Module._compile (node:internal/modules/cjs/loader:1101:14)
    at Object.Module._extensions..js (node:internal/modules/cjs/loader:1153:10)
    at Module.load (node:internal/modules/cjs/loader:981:32)
    at Function.Module._load (node:internal/modules/cjs/loader:822:12)
    at Module.require (node:internal/modules/cjs/loader:1005:19) {
  code: 'MODULE_NOT_FOUND',
  requireStack: [
    'D:\\ethereum\\Dkfuwq\\node_modules\\Koa\\node_modules\\content-disposition\\index.js',
    'D:\\ethereum\\Dkfuwq\\node_modules\\Koa\\lib\\response.js',
    'D:\\ethereum\\Dkfuwq\\node_modules\\Koa\\lib\\application.js',
    'D:\\ethereum\\Dkfuwq\\app.js'
  ]
}