code: def fetch_top_tracks_of_artist(self, artist_id, terr=KKBOXTerritory.TAIWAN):
          '''
          Fetcher top tracks belong to an artist by given ID.
  
          :param artist_id: the artist ID.
          :type artist_id: str
          :param terr: the current territory.
          :return: API response.
          :rtype: dict
  
          See 'https://docs-en.kkbox.codes/v1.1/reference#artists-artist_id-toptracks'
          '''
          url = 'https://api.kkbox.com/v1.1/artists/%s/top-tracks' % artist_id
          url += '?' + url_parse.urlencode({'territory': terr})
          return self.http._post_data(url, None, self.http._headers_with_access_token()f fetch_top_tracks_of_artist(self, artist_id, terr=KKBOXTerritory.TAIWAN):
          '''
          Fetcher top tracks belong to an artist by given ID.
  
          :param artist_id: the artist ID.
          :type artist_id: str
          :param terr: the current territory.
          :return: API response.
          :rtype: dict
  
          See 'https://docs-en.kkbox.codes/v1.1/reference#artists-artist_id-toptracks'
          '''
          url = 'https://api.kkbox.com/v1.1/artists/%s/top-tracks' % artist_id
          url += '?' + url_parse.urlencode({'territory': terr})
          return self.http._post_data(url, None, self.http._headers_with_access_token())
docs: Fetcher top tracks belong to an artist by given ID.
  
          :param artist_id: the artist ID.
          :type artist_id: str
          :param terr: the current territory.
          :return: API response.
          :rtype: dict
  
          See 'https://docs-en.kkbox.codes/v1.1/reference#artists-artist_id-toptracks'