1.   public function create_user($values, $expected)
  2.   {
  3.     // Validation for passwords
  4.     $extra_validation = Model_User::get_password_validation($values)
  5.       ->rule('password', 'not_empty');
  6.  
  7.     return $this->values($values, $expected)->create($extra_validation);
  8.   }