Automatically Set Approvers based on Requestor's Property using Scriptrunner

[Alvin]

Hello , I am new to JIRA, can someone help me with my problem

I want to create a simple post function on JIRA Service Desk that automatically sets the Approvers Field based on the requestor's manager. 

(i.e. if Requestor 1 creates a ticket, then the post function will read the property of requestor 1 and then finds the Manager and automatically set it to Approvers Field)

Any comments/suggestions are really appreciated. If you can also provide a sample post-function code for this one, that would be great. 

Thanks!