Describe mechanism used when receiving response

This looks like a very interesting project, one that would replace some custom code we have where we create actual SQS queues for each requester (so as to send the responses to the correct requester).

Unfortunately, the projects where we need this are all in Python, and we don't want to add dependencies to `py4j` or the like.

Your documentation and the [introductory post](https://aws.amazon.com/blogs/compute/simple-two-way-messaging-using-the-amazon-sqs-temporary-queue-client/) give some clues about the overall mechanism:

> when sending a message, the virtual queue name is attached as an attribute to the message;

Ok, I can understand that, and how the receiver would then use the same attribute when sending the response. But when **receiving** a message, what is the mechanism actually used (on the real SQS queue) to filter messages for the requester?

BTW, my assumption is that we have distributed requesters; is that correct?

It would be good to provide some explanation about the underlying mechanism that is used.