Running jupyterlab via uv tool install

I tried to get jupyterlab working via uv tool install today and ran into some sharp edges.

You can start like this:

uv tool install jupyterlab

That ran for a while and output:

Installed 4 executables: jlpm, jupyter-lab, jupyter-labextension, jupyter-labhub

It also gave me a warning about my PATH. I fixed that with:

uv tool ensure-path

On one other machine this didn't work because it refused to over-write a previous installation. The fix was to run uv tool install with --force:

uv tool install jupyterlab --force

Now we can start jupyterlab with:

jupyter-lab

This was the biggest sticking point for me. Jupyter has a useful magic command for installing packages:

%pip install llm

When I tried to run this I got this error:

/Users/simon/.local/share/uv/tools/jupyterlab/bin/python: No module named pip

It turns out we have an installation with no pip binary.

There may be a better way to do this, but I found that this worked, run in a Jupyter notebook cell:

import subprocess, sys
subprocess.check_call([sys.executable, "-m", "ensurepip"])

After I ran this, the %pip magic command worked as expected - I didn't even need to restart the kernel.

I opened an issue about this and submitted a PR with a potential fix.

Created 2025-03-08T14:58:18-06:00, updated 2025-03-08T15:31:00-06:00 · History · Edit