code: def __calculate_within_cluster_score(self, index_cluster, difference):
          
  
          score = self.__calculate_cluster_difference(index_cluster, difference)
          if len(self.__clusters[index_cluster]) == 1:
              return float('nan')
          return score / (len(self.__clusters[index_cluster]) - 1)
docs: !
          @brief Calculates 'A' score for the specific object in cluster to which it belongs to.
  
          @param[in] index_point (uint): Index point from input data for which 'A' score should be calculated.
          @param[in] index_cluster (uint): Index cluster to which the point is belong to.
  
          @return (float) 'A' score for the object.