SYNCHRONIZED
Locks are used to ensure that only a single thread can initialize the Lazy instance.
© 2010–2017 JetBrains s.r.o.
Licensed under the Apache License, Version 2.0.
https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-lazy-thread-safety-mode/-s-y-n-c-h-r-o-n-i-z-e-d.html