How to use code to implement the function of colormap image and overlay two images like itksnap

this my code, why it goes wrong?What code should I write
colormap = sitk.Colormap(4) # jet

mapped_image = sitk.ScalarToRGBColormap(im1, colormap)

image_viewer.Execute(mapped_image)

Hello @ljjiayou,

Please see the SimpleITK jupyter notebooks repository, specifically this notebook, section titled Overlay scalar image onto another via color map.

thank you very much