Using Python Tools

Overview

Questions

• What is a Python tool?
• How can I install, run, and manage a Python tool?

Objectives

• Install and run a Python tool with uv.

What is a Python tool?

---

A Python tool is just a Python package that provides a command line interface (CLI). These tools can be run directly with uv or installed globally just like any other command line application.

Run a Python tool with uv

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The pycowsay package provides a command line interface for a talking cow based on text provided by the user. The uv command shown below will run the pycowsay package with the provided text. Notice there is no need to install Python, create a virtual environment, activate the virtual environment, and install the pycowsay package into the environment. You just use uv to directly run the pycowsay package; uv will handle installation and virtual environment creation automatically.

BASH

$ uv tool run pycowsay hello there!

OUTPUT

  ------------
< hello there! >
  ------------
   \   ^__^
    \  (oo)\_______
       (__)\       )\/\
           ||----w |
           ||     ||

An equivalent command to uv tool run is uvx which is demonstrated below.

BASH

$ uvx pycowsay hello there!

OUTPUT

  ------------
< hello there! >
  ------------
   \   ^__^
    \  (oo)\_______
       (__)\       )\/\
           ||----w |
           ||     ||

Here is a demo of using uvx to run the pycowsay tool:

Install, upgrade, and remove a Python tool

---

Use the uv install command to globally install a Python tool on your system. To demonstrate this, the command shown below installs the Genja tool which is a static website generator built with Python.

BASH

$ uv tool install genja

The genja tool can now be run directly from the command line without invoking uv such as:

BASH

$ genja --version

OUTPUT

25.3

Use the list command to show all the tools installed by uv:

BASH

$ uv tool list

OUTPUT

genja v25.3.1
- genja 

Use the upgrade command to upgrade a single Python tool or all of the installed tools:

BASH

# Upgrade a single tool
$ uv tool upgrade genja

# Upgrade all installed tools
$ uv tool upgrade --all

To remove a tool, use the uninstall command:

BASH

$ uv tool uninstall genja

Challenge

Challenge

What happens if you run uvx jupyter notebook in your terminal?

Show me the solution

You should see a Jupyter notebook running in your web browser. The file browser for the notebook shows the contents of the directory where the uvx command was run. This is the easiest way to run a Jupyter notebook to explore Python code.

Key Points

• A Python package with a command-line interface is a Python tool.
• A Python tool can be installed, run, and managed with the uv tool command.
• With uv, Python tools can be easily installed on any operating system.