How to get access token for Azure DevOps from Microsoft Teams app

Question

I integrated an MS Teams using tab with an angular app that I created. I am able to authenticate the user within the Microsoft teams app and to get logged in user token using Microsoft Teams Javascript SDK. 

https://docs.microsoft.com/en-us/javascript/api/overview/msteams-client?view=msteams-client-js-latest#using-the-sdk

I don't know how to integrate azure DevOps with Microsoft teams can someone help.