text: 'use strict'
  
  const countProps = function(obj) {
    return Object.keys(obj).length;
  };
  
  console.log(countProps({}));
  
  console.log(countProps({ name: 'Mango', age: 2 }));
  
  console.log(countProps({ mail: 'poly@mail.com', isOnline: true, score: 500 }));
  