Installing Python 3 on Windows

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First, download the latest version of Python 3.6 from the official website. If you want to be sure you are installing a fully up-to-date version, click the Downloads > Windows link from the home page of the Python.org web site .

By design, Python installs to a directory with the version number embedded, e.g. Python version 3.6 will install at C:\Python36\, so that you can have multiple versions of Python on the same system without conflicts. Of course, only one interpreter can be the default application for Python file types. It also does not automatically modify the PATH environment variable, so that you always have control over which copy of Python is run.

Typing the full path name for a Python interpreter each time quickly gets tedious, so add the directories for your default Python version to the PATH. Assuming that your Python installation is in C:\Python36\, add this to your PATH:

C:\Python36\;C:\Python36\Scripts\

You can do this easily by running the following in powershell:

[Environment]::SetEnvironmentVariable("Path", "$env:Path;C:\Python36\;C:\Python36\Scripts\", "User")

This is also an option during the installation process.

The second (Scripts) directory receives command files when certain packages are installed, so it is a very useful addition. You do not need to install or configure anything else to use Python. Having said that, I would strongly recommend that you install the tools and libraries described in the next section before you start building Python applications for real-world use. In particular, you should always install Setuptools, as it makes it much easier for you to use other third-party Python libraries.

Working with Python 3

At this point, you may also have Python 2.7 installed.

$ python

This will launch the Python 2 interpreter.

$ python3

This will launch the Python 3 interpreter.

Setuptools + Pip

The two most crucial third-party Python packages are setuptools and pip, which let you download, install and uninstall any compliant Python software product with a single command. It also enables you to add this network installation capability to your own Python software with very little work.

All supported versions of Python 3 include pip, so just make sure it’s up to date:

python -m pip install -U pip

Pipenv & Virtual Environments

The next step is to install Pipenv, so you can install dependencies and manage virtual environments.

A Virtual Environment is a tool to keep the dependencies required by different projects in separate places, by creating virtual Python environments for them. It solves the “Project X depends on version 1.x but, Project Y needs 4.x” dilemma, and keeps your global site-packages directory clean and manageable.

For example, you can work on a project which requires Django 1.10 while also maintaining a project which requires Django 1.8.

So, onward! To the Pipenv & Virtual Environments docs!


This page is a remixed version of another guide, which is available under the same license.