function isDirector($value) { $directors = array("Steven Spielberg", "Martin Scorsese", "George Lucas", "Christopher Nolan"); return in_array($value, $directors); } // Example usage: $directorName = "Steven Spielberg"; if (isDirector($directorName)) { echo "Valid director: " . $directorName; } else { echo "Invalid director: " . $directorName; }The package library used for isDirector validation in PHP can vary depending on the specific validation needs of the project. Some popular options include the Symfony Validation component, Laravel Validation, or the Respect Validation library.