def save_fanart(self, show_obj, which=None):
        # type: (sickbeard.tv.TVShow, Optional[AnyStr]) -> bool
        """
        Downloads a fanart image and saves it to the filename specified by fanart_name
        inside the show's root folder.

        show_obj: a TVShow object for which to download fanart
        """

        # use the default fanart name
        fanart_path = self.get_fanart_path(show_obj)

        fanart_data = self._retrieve_show_image('fanart', show_obj, which,
                                                img_cache_type=sickbeard.image_cache.ImageCache.FANART)

        if not fanart_data:
            logger.log(u"No fanart image was retrieved, unable to write fanart", logger.DEBUG)
            return False

        return self._write_image(fanart_data, fanart_path)