Colorbrewer's qualitative/discrete colormaps ("Accent", "Dark2", "Paired", "Pastel1", "Pastel2", "Set1", "Set2", "Set3") are now implemented as ListedColormap instead of LinearSegmentedColormap.

To use these for images where categories are specified as integers, for instance, use:

plt.imshow(x, cmap='Dark2', norm=colors.NoNorm())