Android Question Admob Mediation With Adcolony

Hey guys

I want to use the Mediation service on Google with adcolony ads.

https://clients.adcolony.com/

https://support.adcolony.com/

I've done all the steps in the adcolony service (add app and get cod and ......)
and I've also done all the steps in the Google service ( make mediation group and set cod and ...)
and my apps display well as Google admob ads.

To display ads from adcolony and google (mediation) , what codes should I add to the program and manifest? ?
What files should I add to the program??

Thank you ?