Exception handling with kotlin launch coroutine

launchWithRetrofit.kt

fun sendCreateUserRequest(firstName: String, lastName: String) {
    launch(parentJob + UI) {
        try {
            val listOfUsers = run(CommonPool) {
                val user = User(firstName, lastName)
                RestClient.apiDefinition.createUser(user).execute()
            }

            toast("Created user id is ${listOfUsers.body()?.id}")
        } catch (ex: IOException) {
            alertWithOkButton("Error with internet connection")
        } catch (ex: RuntimeException) {
            alertWithOkButton("Error with parsing server response")
        }
    }
}