打包项目失败

package.json

@@ -26,6 +26,7 @@
     "code-prettify": "^0.1.0",
     "codemirror": "^5.64.0",
     "connected-react-router": "4.4.1",
+    "cross-port-killer": "^1.0.1",
     "css-loader": "^3.5.2",
     "dompurify": "^2.3.3",
     "dotenv": "4.0.0",
@@ -204,7 +205,7 @@
     "babel-preset-stage-2": "^6.24.1",
     "compression-webpack-plugin": "^1.1.12",
     "concat": "^1.0.3",
-    "cross-env": "^7.0.3",
+    "cross-env": "^5.1.1",
     "happypack": "^5.0.1",
     "less": "^3.9.0",
     "less-loader": "^4.1.0",

src/modules/404/Shixunnopage.js

@@ -1,6 +1,8 @@
 import React, { Component } from 'react';
 import { TPMIndexHOC } from '../tpm/TPMIndexHOC';
 import { SnackbarHOC, getImageUrl } from 'educoder';
+import Loading from "../../Loading";
+
 
 class http500 extends Component {
     constructor(props) {