How can I add Google Map as Basemap in my application using 4x javascript API

[SHASHIKANTKUMAR]

I want to add Google map as Basemap in my application by using  BasemapGallery Widget. As I am using this in older application by 3x Api.
But in 4x api version , I have not found any solution or example for adding Google  Map as Basemap. ?
Please help me out

[ReneRubalcava]

This isn't allowed via Google ToS

https://developers.google.com/maps/faq#tos_tiles