class User extends CActiveRecord { public function afterFind() { // Perform some operation on the retrieved data $this->age_in_years = floor((time() - strtotime($this->dateOfBirth)) / (365*24*60*60)); } }In this example, the afterFind method is used to calculate the age of a user based on their date of birth. The method uses the strtotime function to convert the date of birth into a Unix timestamp, and then calculates the number of years between the current time and the date of birth. The calculated age is then stored in a new property called age_in_years. The CActiveRecord class is part of the Yii PHP framework, which is a package library for web development.