text: function inheritingAndReplacingToString() {
      class Person{
          constructor(name, email){
              this.name = name;
              this.email = email;
          }
  
          toString(){
              return `${this.constructor.name} (name: ${this.name}, email: ${this.email})`;
          }
      }
  
      class Teacher extends Person{
          constructor(name, email, subject){
              super(name, email);
              this.subject = subject;
          }
  
          toString(){
              return super.toString().substr(0, super.toString().length-1) + `, subject: ${this.subject})`;
          }
      }
  
      class Student extends Person{
          constructor(name, email, course){
              super(name, email);
              this.course = course;
          }
  
          toString(){
              return super.toString().substr(0, super.toString().length-1) + `, course: ${this.course})`;
          }
      }
  
      return {Person, Student, Teacher}
  }
  