E/File$object: kotlinx.coroutines.channels.ClosedSendChannelException: Channel was closed
        at kotlinx.coroutines.channels.Closed.getSendException(AbstractChannel.kt:1048)
        at kotlinx.coroutines.channels.AbstractSendChannel.offer(AbstractChannel.kt:166)
        at kotlinx.coroutines.channels.ChannelCoroutine.offer(ChannelCoroutine.kt)

channelFlow<List<Foo>> {
    updateStream().subscribe({ offer(it) }, {})
    awaitClose {
        // unsubscribe
    }
}