protected function regexValidator($regex, $requirement)
    {
        $validator = $this->app->make(RegexValidator::class, [$regex]);
        $validator->setRequirementString(RegexValidator::E_DOES_NOT_MATCH, $requirement);
        $validator->setErrorString(RegexValidator::E_DOES_NOT_MATCH, $requirement);

        return $validator;
    }