An utterly unnecessary custom colormap library inspired by the psychedelic sea slugs.
pip install nudibranch
from nudibranch import cm
from nudibranch.cm import berghia
aurea_r = cm.get_cmap('aurea_r')
ax.imshow(z, cmap=aurea_r)
ax.imshow(z, cmap=berghia)
etc
David Dempsey (Civil and Natural Resource Engineering, University of Canterbury)