Function update_or_recreate_consumer 

async fn update_or_recreate_consumer(
    config: &ConsumerClientConfig,
    num_partitions: usize,
    stream: &Stream<Info>,
) -> Result<Consumer<Config>, Error>

Updates a consumer to give it a subset of the parts in the stream partition, compared to all other consumers currently registered in the stream. If the consumer no longer exists, possibly as a result of the inactive_threshold, the consumer is recreated.