Functions in SAP ABAP RESTful Application Programming Model ?

Hello Experts,

Did any one try on "how Functions work in ABAP RESTful Application Programming Model" ?

I found below information theoretically but no examples to try ..

If yes, please share examples.

https://help.sap.com/viewer/923180ddb98240829d935862025004d6/Cloud/en-US/d401150cfdb1454d9f55d80aead9579a.html