This happen when i type node index.js

module.js:549
throw err;
^

Error: Cannot find module ‘request’
at Function.Module._resolveFilename (module.js:547:15)
at Function.Module._load (module.js:474:25)
at Module.require (module.js:596:17)
at require (internal/module.js:11:18)
at checkLatestVersion (/home/pi/matrix-os/index.js:1001:3)
at Object. (/home/pi/matrix-os/index.js:16:1)
at Module._compile (module.js:652:30)
at Object.Module._extensions…js (module.js:663:10)
at Module.load (module.js:565:32)
at tryModuleLoad (module.js:505:12)