Failed at the appauth-react@0.1.0 start script

[gowthamaswath]

npm start is giving the following error
'PORT' is not recognized as an internal or external command,
operable program or batch file.
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! appauth-react@0.1.0 start: PORT=4200 react-scripts start
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the appauth-react@0.1.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output
above.

npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\M1043931\AppData\Roaming\npm-cache_logs\2020-11-19T09_23_30_027Z-debug.log

[kdhttps]

try to run it in gitbash or powershell