Running jupyterlab via uv tool install

Author: simonw

jupyter/jupyterlab-uv-tool-install.md

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+# Running jupyterlab via uv tool install
+
+I tried to get [jupyterlab](https://jupyter.org/install) working via `uv tool install` today and ran into some sharp edges.
+
+You can start like this:
+```bash
+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`:
+```bash
+uv tool install jupyterlab --force
+```
+Now we can start jupyterlab with:
+```bash
+jupyter-lab
+```
+## Getting %pip to work
+
+This was the biggest sticking point for me. Jupyter has a useful magic command for installing packages:
+
+```python
+%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:
+
+```python
+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.