getThemeChoices example

$this->io = new SymfonyStyle($input, $output);
        $helper = $this->getHelper('question');

        if ($input->getOption('sales-channel') && $input->getOption('all')) {
            $this->io->error('You can use either --sales-channel or --all, not both at the same time.');

            return self::INVALID;
        }

        if (!$themeName) {
            $question = new ChoiceQuestion('Please select a theme:', $this->getThemeChoices());
            $themeName = $helper->ask($input, $output, $question);
        }
        \assert(\is_string($themeName));

        /** @var SalesChannelCollection $salesChannels */
        $salesChannels = $this->salesChannelRepository->search(new Criteria(), $this->context)->getEntities();

        if ($input->getOption('all')) {
            $selectedSalesChannel = $salesChannels;
        } else {
            if (!$salesChannelOption) {