How to update list value based two fields vlaues

[Muna Khamis]

hello, 

i'm new to groovy & trying to update "single select list" value based two "single select list" fields on postfunction during a transition

[Nic Brough -Adaptavist-]

There's a sample script with the basics at https://library.adaptavist.com/entity/update-a-single-select-drop-down-custom-field

[Muna Khamis]

thanks, but unable to find script to update values of the values of (Single Select List) based on (Single Select List2) to update (Single Select List3). appreciate the support here