/**
* _.isUndefined()
* It checks if the parameter passed to it is undefined or not.
* If the parameter passed is undefined
* it return true otherwise it returns false.
**/
import * as _ from 'underscore'
let value = null
console.log(_.isUndefined(value))
// Output: false
value = undefined
console.log(_.isUndefined(value))
// Output: true