Can't find blockingLazy() method in kotlin

In the ‘Standard Delegates’ section of the Delegation Properties page, there is one sentence says:

If you want thread safety, use blockingLazy() instead: it guarantees that the values will be computed only in one thread and that all threads will see the same value.

But I searched the kotlin standard library and can’t find the blockingLazy() method.

I was using the kotlin 1.9.10:

$ kotlin -version
Kotlin version 1.9.10-release-459 (JRE 17.0.8+9-LTS-211)

and kotlin standard library 1.9.0:

<dependency>
    <groupId>org.jetbrains.kotlin</groupId>
    <artifactId>kotlin-stdlib</artifactId>
    <version>1.9.0</version>
</dependency>

It seems that kotlin has removed the blockingLazy method.

I did find a lazy method which allow passing a lock parameter. It should be the new way to use a blocking lazy.

So I implement a thread-safe version here:

class ThreadSafeLazyExample {
    init {
        println("Created!")
    }

    private val lazyLock: Int = 1

    // a thread safe lazy
    val lazyStr: String by lazy(lazyLock) {
        println("computed!")
        "my lazy"
    }
}

fun main() {
    val sample = ThreadSafeLazyExample()
    println("lazyStr is ${sample.lazyStr}")
    println(" =${sample.lazyStr}")
}