If hostname is None, look at label_to_hostname setting

def _get_hostname(self, hostname, sample, scraper_config):
        """
        If hostname is None, look at label_to_hostname setting
        """
        if (
            hostname is None
            and scraper_config['label_to_hostname'] is not None
            and scraper_config['label_to_hostname'] in sample[self.SAMPLE_LABELS]
        ):
            hostname = sample[self.SAMPLE_LABELS][scraper_config['label_to_hostname']]
            suffix = scraper_config['label_to_hostname_suffix']
            if suffix is not None:
                hostname += suffix

        return hostname