text: const Employee = function () {
      let _username = "user";
      let _mailhost = "example.com";
      this.firstname = "";
      this.lastname = "";
      Object.defineProperty(this, "email", {
          get: function () {
              return `${_username}@${_mailhost}`;
          },
          set: function (addr) {
              var components = String(addr).split("@");
              _username = components[0] || "user";
              _mailhost = components[1] || "example.com";
          }
      });
  };
  const employee = new Employee();
  console.log(employee.email);
  employee.email = "amgilder@cs.unh.edu";
  console.log(employee.email);
  console.log(employee._username);