Python in a Windows Universe

Up-to-date, easy-to-read guide for building Python developer-friendly ecosystems in Windows 10.

This guide is a community project ...

Brought to you to courtsey of Code For Tallahassee, a non-profit Code For America Bridgade located in Florida’s‘ beautiful capital city.

The guide is a work in progress ...

The plan is to expand to include other Python in Windows related topics over time. We welcome new contributions, corrections and other feedback from the Python community at large; be respectful, but please don’t be shy.

This project is licensed under Creative Commons ...

https://i.creativecommons.org/l/by-nc-sa/4.0/88x31.png

Quick Start

Step 1: Download & Install Python 2 & 3

Python 2.7 (32-bit)

  1. Click on the following link to download Python 2.7 ... https://www.python.org/ftp/python/2.7.12/python-2.7.12.msi
  2. Double-click on the downloaded file to install it and use all of the default settings.

Python 3.5 (32-bit)

Attention

Mark the “Install Python 3.5 PATH” checkbox at the bottom of the first dialog box in the Python 3.5 install wizard.

  1. Click on the following link to download Python 3.5 ... https://www.python.org/ftp/python/3.5.2/python-3.5.2.exe
  2. Double-click on the downloaded file to install it. With the exception of the “Install Python 2.5 PATH” checkbox, use all of the default settings.

Step 2: Validate the Default Interpreter

Use Ctrl-z to exit

Press [Ctrl]-z where you see the ^z symbol to exit out of the Python Interpreter.

  1. Open the command prompt and open the default interpreter:

    C:\> python
Python 3.5.2 (v3.5.2:4def2a2901a5, Jun 25 2016, 22:01:18) [MSC v.1900 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> ^z

  2. Open the Python 2.7 interpreter:

    C:\> c:\Python27\python.exe
Python 2.7.12 (v2.7.12:d33e0cf91556, Jun 27 2016, 15:19:22) [MSC v.1500 32 bit (Intel)] on win32
Type "help", "copyright", "credits" or "license" for more information.
>>> ^z

Step 3: Install a Virtual Environment Manager

  1. Install virtualenvwrapper-win ...
C:\> cd \temp
C:\> git clone https://github.com/davidmarble/virtualenvwrapper-win.git
C:\> cd virtualenvwrapper-win
C:\> python setup.py install
C:\> copy scripts\mkproject.bat %USERPROFILE%\AppData\Local\Programs\Python\Python35-32\Scripts
C:\> notepad %USERPROFILE%\AppData\Local\Programs\Python\Python35-32\Scripts\workon.bat
  1. Add the “doskey workoff=deactivate” line after “@echo off”.
@echo off

doskey workoff=deactivate

if not defined WORKON_HOME (
    set "WORKON_HOME=%USERPROFILE%\Envs"
)

Step 4: Install Interactive Computing Environments

Install IPython & Jupyter Notebook ...

C:\> pip install jupyter

C:\> mkvirtualenv -p c:\Python27\python.exe cp27
C:\> setprojdir c:\%USERNAME%\projects\cp27
C:\> workon cp27
C:\> pip install jupyter

C:\> mkproject cp35

Step 5: Install a Version Control System

Note

Download will start automatically once you click on the link

  1. Click on the following link to download Git ... https://git-scm.com/download/win
  2. Double-click on the downloaded file to install it and use all of the default settings.

Step 6: Install Unix Utilities

  1. Click on the following link to download UnxUtils ... https://sourceforge.net/projects/unxutils/files/latest/download
  2. Click on the downloaded file to open it.
  3. Right-click anywhere in the whitespace on right pane of file explorer and select “Extract All”.
  4. When setting the destination folder browse to “C:Program Files (x86)”.
  5. Press [Win]-s then type “env”
  6. Select “Edit the System Environment Variables: Control Panel”
  7. Click on the “Environment Variables” button
  8. Click on the “Path” variable under “System Variables”
  9. Click on the “Edit” button
  10. Click on the “New” button
  11. Type “C:Program Files (x86)UnxUtilsusrlocalwbin” and press [Enter]
  12. Click the “Move Up” button until it is above “%SystemRoot%system32”
  13. Verify the sort command is the one that comes with unxutils by typing the following ...
C:\>whereis sort
C:\Program Files (x86)\UnxUtils\usr\local\wbin\sort.exe

Step 7: Install a Regular Expression Debugger

  1. Click on the following link to download Kodos ... https://sourceforge.net/projects/kodos/files/latest/download?source=files
  2. Double-click on the downloaded file to install it and use all of the default settings.

Step 8: Install a Tool for Getting & Sending Files using URL Syntax

  1. Click on the following link to download cURL ... http://www.confusedbycode.com/curl/#downloads
  2. Check the “I am not a robot” checkbox.
  3. Click on the curl-7.46.0-win32.exe button on the “Administrator Privileges (free) row.
  4. Double-click on the downloaded file to install it and use all of the default settings.

Step 9: Install a Code & Markup Editor

  1. Click on the following link to download Python 2.7 ... https://download.sublimetext.com/Sublime%20Text%20Build%203114%20Setup.exe
  2. Double-click on the downloaded file to install it.
  3. Set the destination directory to ...
c:\Program Files (x86)\Sublime Text 3
  1. Press and release the [Win] key and righ-click on the on the “Sublime Text 3” icon and select “More” then “Pin to Taskbar”. Click on the new icon on your taskbar (brown square with an orange “S” in the middle).
  2. From the menu at the top select “View” –> “Show Console”.
  3. Click in the console at the bottom of the screen and paste in the following code and press [Enter]
import urllib.request,os,hashlib; h = '2915d1851351e5ee549c20394736b442' + '8bc59f460fa1548d1514676163dafc88'; pf = 'Package Control.sublime-package'; ipp = sublime.installed_packages_path(); urllib.request.install_opener( urllib.request.build_opener( urllib.request.ProxyHandler()) ); by = urllib.request.urlopen( 'http://packagecontrol.io/' + pf.replace(' ', '%20')).read(); dh = hashlib.sha256(by).hexdigest(); print('Error validating download (got %s instead of %s), please try manual install' % (dh, h)) if dh != h else open(os.path.join( ipp, pf), 'wb' ).write(by)
  1. From the menu select “Preferences” –> “Package Control”
  2. Press “i” [Enter] to “Install Package”
  3. Type “flake8” and select “Python Flake8 Lint”
  4. From the menu select “Preferences” –> “Package Control”
  5. Press “i” [Enter] to “Install Package”
  6. Type “rest” and select “RestructuredText Improved”
  7. From the menu select “Preferences” –> “Package Control”
  8. Press “i” [Enter] to “Install Package”
  9. Type “sidebar” and select “SideBarEnhancements”
  10. From the menu select “File” –> “New File”
  11. Press [Ctrl]-s to “Save As”
  12. Type “temp.py”
  13. From the menu select “Preferences” –> “Settings - More” –> “Syntax Specific - User”
  14. Copy & Paste the text below into the main editor window
{
    "rulers": [72, 79],
    "translate_tabs_to_spaces": true,
    "draw_white_space": "all",
    "tab_size": 4
}
  1. Press [Ctrl]-f then s to save the changes.
  2. Press [Ctrl]-w to close the window.
  3. If you have administrator right to your machine ... Right-click [Windows Start] and select “Command Prompt - Admin” Click the “Yes” button on the “Do you want to allow this application to make changes to your PC?” Copy and paste the following into the command prompt ...

Attention

If you installed Sublime Text 3 somewhere other than “C:Program Files (x86)Sublime Text 3” then modify the SET statement below accordingly.

       @echo off
       SET st3Path=C:\Program Files (x86)\Sublime Text 3\sublime_text.exe

       rem add it for all file types
       @reg add "HKEY_CLASSES_ROOT\*\shell\Open with Sublime Text 3"         /t REG_SZ /v "" /d "Edit with Sublime Text 3"   /f
       @reg add "HKEY_CLASSES_ROOT\*\shell\Open with Sublime Text 3"         /t REG_EXPAND_SZ /v "Icon" /d "%st3Path%,0" /f
       @reg add "HKEY_CLASSES_ROOT\*\shell\Open with Sublime Text 3\command" /t REG_SZ /v "" /d "%st3Path% \"%1\"" /f

       rem add it for folders
       @reg add "HKEY_CLASSES_ROOT\Folder\shell\Open with Sublime Text 3"         /t REG_SZ /v "" /d "Edit with Sublime Text 3"   /f
       @reg add "HKEY_CLASSES_ROOT\Folder\shell\Open with Sublime Text 3"         /t REG_EXPAND_SZ /v "Icon" /d "%st3Path%,0" /f
       @reg add "HKEY_CLASSES_ROOT\Folder\shell\Open with Sublime Text 3\command" /t REG_SZ /v "" /d "%st3Path% \"%1\"" /f

20. Close the Command window.

Congratulations!

You’re Windows 10 Python ecosystem is ready to rumble.

Python Installation

Python version 2 or 3?

Tip

Recommendation: Both

  • Develop your coding habbits in Python 3; it’s not going away.
  • Keep 2.7 around; you can’t kill it, it’s immortal. [1]
  • If your code’s going public consider supporting both.
[1]Despite claims that Python 2’s scheduled End Of Life date (EOL, sunset date) is in 2020.

See also

Should I use Python 2 or Python 3 for my development activity?

Python 32 or 64-bit version?

Tip

Recommendation: 32-bit, unless ...

  • You’re willing to trade away memory for performance (64-bit can consume up twice the memory).
  • You work with really large data sets and need access to more than 4GB of system memory.

Install Python

Install Python 2.7

Double-click on the Python 2.7 MSI that you downloaded to launch the installer, and click the “Next” button at each screen to accept the default settings.

_images/python27_screen1.png _images/python27_screen2.png _images/python27_screen3.png

Note

At this point you may see a Windows pop-up dialog box, “Do you want to allow this application install software on your PC?” If the “Verified Publisher” is set to “Python Software Foundation” then click the “Yes” button.

See also

User Account Control

_images/python27_screen4.png

Click “Finish” to complete the Python 2.7 installation.

Install Python 3.5

Double-click on the Python 3.5 executable (.exe) that you downloaded to launch the installer.

Note

On the first screen make sure to check the “Add Python 3.5 to PATH” checkbox.

_images/python35_screen1.png

Click on the “Install Now” section to begin.

Note

At this point you may see a Windows pop-up dialog box, “Do you want to make change to your PC?” If the “Verified Publisher” is set to “Python Software Foundation” then click the “Yes” button.

_images/python35_screen2.png

Click “Finish”

Congratulations!

You have now installed both Python 2 & 3.

Python Packages

“Python is known for it’s ‘batteries included’ philosophy and has a rich standard library. However, being a popular language, the number of third party packages is much larger than the number of standard library packages. So it eventually becomes necessary to discover how packages are used, found ...”

—Hitchiker’s Guide to Packaging

PyPI

The Python Package Index (PyPI), formerly known as the Cheeseshop, is a central repository containing tens of thousands of ready to install Python community projects and distributions. It will become an integral part of your Python ecosystem.

pip

Pip works with PyPI, it’s used to install and manage Python packages. Pip replaces easy_install.

Action Command
install package pip install <pkg-name>
uninstall package pip uninstall <pkg-name>
upgrade package pip install -U <pkg-name>

Pip was installed as part of Python, but now we need to upgrade it to make sure we are using the latest version:

pip install --upgrade pip
Command Action
pip list List all packages installed in the current environment.
pip search <text> List all PyPI packages whose name or summary contains <text>.
pip show <pkg-name> ... Show information about one or more installed packages.

Go head and practice:

pip list
pip search web2py
pip show pip

Wheels

A Wheel is python distribution standard that doesn’t require building or complation; wheels replace eggs . Wheel has an official PEP; Egg doesn’t.

Use Wheel if you try to install a package from PyPI and you see this ...

Warning

error: Unable to find vcvarsall.bat

The package is probably a C extension and it can’t find a compiler in Windows. The easiest way to install these types of packages is to download the Wheel file from the Unofficial Windows Binaries for Python Extension Packages.

For example, locate the pandas, a data analysis package. The Wheel files look something like this:

pandas-0.18.1-cp27-cp27m-win32.whl

The Wheel file format is is defined in PEP 425 as:

{distribution}-{version}(-{build tag})?-{python tag}-{abi tag}-{platform tag}.whl

“When people speak of Python they often mean not just the language but also the CPython implementation. Python is actually a specification for a language that can be implemented in many different ways.”

—Official Python Guide

File Name Package-Version Python-Version 32/64-bit?
pandas-0.18.1-cp27-cp27m-win32.whl 0.18.1 Python 2.7 32-bit
pandas-0.18.1-cp27-cp27m-win_amd64.whl 0.18.1 Python 2.7 64-bit
pandas-0.18.1-cp35-cp35m-win32.whl 0.18.1 Python 3.5 32-bit
pandas-0.18.1-cp35-cp35m-win_amd64.whl 0.18.1 Python 3.5 64-bit

Once you download the correct Wheel file for your Python version & architecture you can install it with pip:

pip install <wheel-filename>

Make sure to include the path when you specify the Wheel file, for example:

pip install c:\users\<username>\downloads\pandas-0.18.1-cp27-cp27m-win32.whl

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.”

—Hitchiker’s Guide to Python, Virtual Environments

Virtual environments not only help manage package versions, but also ensure the correct version of the Python intepreter is associated with a project.

  • virtualenv is a tool to create these isolated Python environments.
  • virualenvwrapper is a set of extensions to Ian Bicking’s virtualenv tool to add the following features:
  1. Organize all of your virtual environments in one place.
  2. Manage virtual environments (create, delete and list).
  3. Allows the use a single command to switch between environments.

Let’s install virtualenwrapper-win:

pip install virtualenvwrapper-win

Virtual Environment Commands

Command Description
mkvirtualenv <project-name> Create a new virtual environment
lsvirtualenv List all existing virtual environments
setprojectdir <path> Associate a project folder with a virtual environment
cdproject Change to the project folder
workon <project-name> Start up a virtual environment
deactivate Shown down the virtual environment

Virtualenvwrapper-win Environment Variables

Default Environment Variables (preset by virtualenvwrapper-win):

WORKON_HOME=%USERPROFILE%\Envs
PROJECT_HOME=%USERPROFILE%\.projects
Variable Description
WORKON_HOME The directory where the virtual environments will be stored.
PROJECT_HOME The project directory associated with a virtualenv.

We recommend creating a generic sanbox environment for both Python 2.7 and the latest Python 3 release. The gives you a environment to play, experiment and learn in, but we suggest creating a separate virtual environment for each Python project that you work with.

Here’s how to setup the Python 3.5 sandbox:

C:\> mkvirtualenv cp35
C:\> setprojectdir %PROJECT_HOME%\cp35
C:\> workon cp35
  1. This creates new virtual environment we chose to call cp35 (stands for CPython ver. 3.5)
  2. This sets the project directory for the virtual environment.
  3. This restarts the virtual environment and moves you into the project directory.

Now let’s setup the Python 2.7 sandbox (remember you can use tab completion to avoid typing in the whole name:

C:\> mkvirtualenv -p c:\python\python27\python.exe
C:\> setprojectdir %PROJECT_HOME%\cp27
C:\> workon cp27

Note

Since our default Python Interpreter is 3.5, we need to use the -p option with mkvirtualenv to indicate which interpreter we want to use for the virtual environment.

Summary

When you want to play in CPython 2.7:

C:\> workon cp25

When you want to switch to CPython 3.5:

C:\> workon cp35

When you want to exit the virtual environment:

C:\> deactivate

When you want to create a virtual environment for a new project:

C:\> mkvirtualenv <name>
C:\> setprojectdir <path>
C:\> workon <name>

Attention

The Windows logo key will appear as [win] in the docs.

Credits ...