How to get the assignment group on SC Task based on Requested_for Location using Workflow script

Hi,

I want to set the assignment group based on Requested for Location. Under the Cmn_Location table I have an custom filed called "Local support group" which is refers to group table. my requirement is, I want to get the Requested for->Location->Local support Group should be set as assignment group of the sc task. how to achieve this by using workflow script. Please help me on this?

Thanks In Advance

Rajesh B