Realistic visible spectrum in Python

I want to include a color bar with a realistic visible spectrum with cmap, something close to:

However, there is no realistic visible spectrum from cmap, one that is closer seems to be nipy_spectral, good looking but not resembling something like above (especially on the width of some color, that there should be some wider some narrower color range observed from a realistic visible spectrum).

https://stackoverflow.com/questions/66898288/realistic-visible-spectrum-in-python April 01, 2021 at 12:07PM