module.exports = function isnan(x) {
  //      discuss at: https://locutus.io/python/isnan/
  // parity verified: Python 3.12
  //     original by: Kevin van Zonneveld (https://kvz.io)
  //          note 1: Returns True if x is NaN (Not a Number)
  //       example 1: isnan(NaN)
  //       returns 1: true
  //       example 2: isnan(42)
  //       returns 2: false
  //       example 3: isnan(Infinity)
  //       returns 3: false

  return Number.isNaN(x)
}