def __init__(self, name, filename=None):
        self.name = name
        super(NamedRequirements, self).__init__(filename=filename)
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.