How to add an image underneath an ACT custom (post) object in Mechanical?

# Retrieve your post object - `post_object`
post_internal_object = post_object.InternalObject
image = post_internal_object.AddImage()
image.SourceType = 1
image.ImagePath = image_path  # Provide complete path to the image to be added.
 
ExtAPI.DataModel.Tree.Refresh()