Third-Party Tools

Python has a large standard library, providing many useful modules right out of the box. But it will never have everything you need. Python also has a huge collection of third-party modules available for you to install.


Python comes with a package manager called pip. The name is a recursive acronym short for Pip Installs Packages.

If you’re using a recent version of Python 3 (3.4 or higher), then you already have a pip3 command that will install packages.

If you’ve installed Python 2.7.10, and you don’t have a pip command, you can install one by running:

$ python2.7 -m ensurepip

Installing packages is as easy as:

$ pip install the_package_name

If you have more than one installation of Python on your machine, be sure you know which pip (or pip3) you are using. Pip will install packages into the Python installation you run it from.


Python packages are available from the Python Package Index, or PyPI, pronounced Pie-Pee-Eye. Pip automatically knows to install from PyPI, but you can manually search or browse PyPI if you need to.


Virtualenv is a third-party tool for isolating Python package installations from each other. If you are working on more than one project, it’s a good practice to keep their package requirements separate. Virtualenv lets you create a virtual Python environment for each project, and install packages separately for each.


find good instructions to link to for virtualenv.