Check out example codes for "Could not initialize class org.jetbrains.kotlin.gradle.plugin.sources.DefaultKotlinSourceSetKt". It will help you in understanding the concepts better.

Code Example 1

buildscript {
ext {
    kotlinVersion = '1.3.72'
    springBootVersion = '2.0.4.RELEASE'
}
repositories {
    mavenCentral()
}
... 
}

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