Getting error on npm build

[umadahmad]

I am getting Error on npm build script
'NODE_ENV' is not recognized as an internal or external command
I am using windows 10

[umadahmad]

I am using Command
"build": "rimraf dist && SET NODE_ENV=production babel src/lib --out-dir dist --copy-files --ignore __tests__,spec.js,test.js,__snapshots__"
because I am windows user , but this command is only deleting dist folder and doing nothing else