Lookups the labels_mapper table to see if replacing the tag name is
        necessary, then returns a "name:value" tag string

def _format_tag(self, name, value, scraper_config):
        """
        Lookups the labels_mapper table to see if replacing the tag name is
        necessary, then returns a "name:value" tag string
        """
        return '%s:%s' % (scraper_config['labels_mapper'].get(name, name), value)