public function setStateMachineName($state_machine_name)
    {
        $name_regex = '/^[a-zA-Z0-9_\.\-]+$/';

        if (!preg_match($name_regex, $state_machine_name)) {
            throw new VerificationError(
                'Only valid characters for state machine names are [a-zA-Z.-_]. Given: ' . $state_machine_name
            );
        }

        $this->state_machine_name = $state_machine_name;

        return $this;
    }