invert-kv 
Invert the key/value of an object. Example:
{foo: 'bar'}→{bar: 'foo'}
Install
$ npm install invert-kv
Usage
const invertKv = require('invert-kv');
invertKv({foo: 'bar', unicorn: 'rainbow'});
//=> {bar: 'foo', rainbow: 'unicorn'}
License
MIT © Sindre Sorhus