text: function Person(name) {
      this.name = name;
  }
  
  let person1 = new Person('Pepe');
  
  console.log(person1.age);
  // person1.age = 22; adding property to the object not to Person's constructor
  Person.prototype.age = 23; // now all the instance created with this contructor are going to have age property
  let person2 = new Person('Emi');
  console.log(person2.age);
  