Thanks for being willing to work on it.

If what is wanted is a way to pipeline shell commands, Python already has that functionality in the pipes module.

So the interesting thing here would be pipelining *non* shell commands, to avoid the shell exploits that using a shell pipeline invites.

The pipes module already has a worked out API, so perhaps it would be useful to see about re-implementing pipe's command execution using subprocess, and expand the API to allow for argv style command specification that would be fed to subprocess using the default shell=False.  This would also presumably allow pipes to be used when there's no bash shell available.

The downside is that we might break current uses of pipes if we replace the shell version of the pipelining with subprocess shell=True, while using subprocess only if the command specifications are argv lists would result in code with a split personality.  But if I were working on it I'd experiment with that approach to see if it made sense.

Other core devs may have other opinions on this :)