Simplest local web-server to map URL parameter to returned XML file?

I want to simulate a web-service which takes a simple URL of the format:

http://<URL-BASE>?ID=12345

It returns XML. My thought is to have a hard-coded mapping between ID values and pre-generated XML files so e.g there is a file 12345.xml stored in some folder.

I'm not a web-developer so what is the easiest way I can do this on my dev machine? I'm not bothered what language or technology but I would prefer it to be self-contained e.g. not having to run IIS/Apache on my PC but a micro-web-server I just run up pointing to a specific data dir, then kill when I'm done.

All suggestions welcome, the less configuration/setup/learning the better. I'm running on Windows. I'm hoping the code itself for this is about 3 lines I just don't want to get sucked into configuring a web-server.