I saw the kotlin document using “_” like this ```...

# announcements

[freddiewang]

I saw the kotlin document using “_” like this

private var _table: Map<String, Int>? = null
public val table: Map<String, Int>
    get() {
        if (_table == null) {
            _table = HashMap() // Type parameters are inferred
        }
        return _table ?: throw AssertionError("Set to null by another thread")
    }