$user = $user->find_user_by_id_oop (2);
        $user->password = "Pass";
        $user->update ();

public function find_user_by_id_oop($user_id)
{
    global $database;
    $result = $database->query ("SELECT * FROM users WHERE id= {$user_id} LIMIT 1");
    $found_user = $result->fetch_object ();

    return $found_user;
}

public function update($userID, $username, $password, $first_name, $last_name, $email)
{
    global $database;
    global $session;
    $name = trim ($database->escape_string ($username));
    $pass = trim ($database->escape_string ($password));
    $firstname = trim ($database->escape_string ($first_name));
    $lastname = trim ($database->escape_string ($last_name));
    $email_address = trim ($database->connection->real_escape_string ($email));

    $query = "UPDATE users SET username='$name' , password='$pass' , first_name='$firstname' , last_name='$lastname' , email='$email_address' where id=$userID";
     $res = $database->query ($query);


    if ($res) {

        $session->message ('Data Updated');
        return $res;

    } else {

        $session->message ('Data Not Updated');

    }

}

public $username, $id, $first_name, $last_name, $password;

$user = new User();