Chapter 14: ExtraPropertiesExtension has changed

It appears there have been changes in how ExtraPropertiesExtension works in the newest version of Android Studio/ the Google Maps template.
This is what the Project build.gradle file looks like in the version I have:

// Top-level build file where you can add configuration options common to all sub-projects/modules.

plugins {
    id '' version '7.1.2' apply false
    id '' version '7.1.2' apply false
    id '' version '1.6.10' apply false
    id '' version '2.0.0' apply false

task clean(type: Delete) {
    delete rootProject.buildDir

Searching the entire project for the string ext.kotlin_version reveals no results, searching for buildscript reveals two results using the Scope option but there are not related to the code presented in the “Ad-Hoc Gradle properties” section.

The work-around is to paste the code block that starts with buildscript to the beginning of the specified file and add the closing curly brace directly after. The kotlin_version part doesn’t seem to be needed, but the other two properties work just fine.