def _last_index(self, s):
        self.set_index(max(0, self._find_one_after_last_labeled_index() - 1))
def show_clusters(clusters, sample, covariances, means, figure=None, display=True):
        """!
        @brief Draws clusters and in case of two-dimensional dataset draws their ellipses.
        @details Allocated figure by this method should be closed using `close()` method of this visualizer.