public static function start()
 {
     $database = "tardissh_mjm287";
     $username = "******";
     $password = "******";
     //:: you are dealing with something that is static
     //you can't use the this because this references the current instance of //an object.  self says to refer to your own class
     self::$connection = new PDO("mysql:host=localhost;dbname={$database}", $username, $password);
     self::$connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
     return self::$connection;
 }
 public function __construct()
 {
     $this->connection = Database_Class::start();
 }