Add/Remove Values on Picklist via Deluge Function/Workflow

Add/Remove Values on Picklist via Deluge Function/Workflow

I'm trying to figure out how to add or remove a value on a picklist within CRM.

For this case, it would need to be done in a workflow function. I see some options for Zoho Creator, but none for Zoho CRM. Are there any functions that can accomplish this?