Colormaps are now available through the .ColormapRegistry accessible via matplotlib.colormaps or matplotlib.pyplot.colormaps.
If you have the name of a colormap as a string, you can use a direct lookup,
matplotlib.colormaps[name] or matplotlib.pyplot.colormaps[name] . Alternatively, matplotlib.colormaps.get_cmap will
maintain the existing behavior of additionally passing through .Colormap instances
and converting None to the default colormap. matplotlib.pyplot.get_cmap will stay as a
shortcut to matplotlib.colormaps.get_cmap.