This demonstrates a user-installed package that will keep the RSP from starting in a single-python RSP Lab container. However, the same user installed package will not prevent a two-python container (as described in sqr-088).
First, please don't, except in the very limited case where you mean to demonstrate the behavior described above.
If you are doing that, pip install git+https://github.com/lsst-sqre/rsp-poison-pill ; then you will have
to shut down your running Lab instance.
If you then start a one-python container, it will fail to start up.
If you start a two-python container, it will run.
Just don't, please? This is not a module intended for long-term maintenance.