https://pyglove.readthedocs.io/en/latest/learn/soop/som/placeholding.html
Symbolic Placeholding - PyGlove
symbolicplaceholding
https://www.jadehoyer.com/artistic-projects/placeholding/view/8896579/1/8896652
Jade Hoyer : ARTISTIC PROJECTS : Placeholding
jadehoyerartisticprojectsplaceholding