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1
How to Set Up Your Python Development Environment on
Ubuntu 14.04
Prepared By: Stephanie Chan, John Dennert, & Anastasia Khudoyarova
Last Edited: July 30, 2014
Version: 1.1

2
Table of Contents
Introduction 3
Formatting Conventions Used 4
Prerequisites 5
Set Up Process 6
● Open the terminal 6
● Check your Python installation 6
● Set up your virtual environment 7
● Setup version control 9
● Set up SSH with Github 9
● Run the code 11
Summary 13
Troubleshooting 14
Additional Resources 15

3
Introduction
The following instructions detail how to set up a Python development environment on Ubuntu
14.04. As a new software engineer at the company, this knowledge will give you the initial setup
necessary to begin contributing and learning about the technologies we use.
Although these instructions strive to be as thorough as possible, it is not intended to be a
comprehensive tutorial for the wide variety of tools and knowledge required to start contributing code.
Instead, we will link to various other resources throughout the instructions should you require more
background information on certain topics. However,reading the additional resources will not be
necessary to complete these instructions.

4
Formatting Conventions Used
We use a number of different visuals throughout the instructions. This section will explain each
visual and how to use them.
● Keystrokes are shown in the following format: CTRL+ALT+T
● Commands that are typed in the terminal window are shown in the dark sections with
white text. The commands can be copied and pasted from these sections.
$ python
● Tips and other resources are shown in the sections with light bulbs. They will provide
additional information and warnings.
●
●
●
● Screenshots will have a figure number and a caption describing its contents.
Figure 1: The Python interactive shell showing Python version 2.7.6
● Yellow text should be replaced with your information (name, e-mail address,etc.).
This is a tip.

5
Prerequisites
● A clean installation of Ubuntu 14.04
● Minimal programming experience and moderate computer proficiency
Ubuntu is a Debian-based Linux operating system. Although experience with
Ubuntu is not necessary to complete these instructions, you may choose to
familiarize yourself with it on their website: http://www.ubuntu.com/

6
Set Up Process
● Open the terminal
To open the terminal, press the following keys: CTRL+ALT+T
Alternatively, you can open the terminal through the GUI. Go to the sidebar and click the Unity
button on the side bar. In the search prompt, type "terminal". It will bring up the Terminal
icon under "Applications". Click the icon to open the terminal.
Learning to use the command line can be tricky and can take a while to get
really good at it. However,learning even the basics can significantly boost your
productivity. For a good command line tutorial visit:
http://cli.learncodethehardway.org/book/
● Check your Python Installation
○ Python should already be installed by default with your operating system. We will be
using Python version 2.7.6 but any 2.x.x version will work. To check the default version
of Python currently installed, type the following command in the terminal:
$ python
This command will launch the Python interactive shell which shows the default version
of Python installed. The output should look similar to Figure 1 below:
Figure 1: The Python interactive shell showing Python version 2.7.6
○ To close the Python interactive shell, type:
>>> exit()

7
To learn more about Python, visit: http://www.python.org and check out
the official documentation.
For a great tutorial that covers Python from the ground up, visit:
http://learnpythonthehardway.org/
● Set up your virtual environment
When working on multiple projects, it is important to keep your Python installations separate for
each project. One project might use one version of a package while another project might use
another version of the same package. This would be a problem if you just had one version of the
package installed globally that all of the projects used. Instead,you will use what’s called a
virtual environment.
○ Install pip
pip is a tool we will use to install and manage Python packages. To install pip, type:
$ sudo apt-get install -y python-pip
Now we can start installing Python packages.
Installing software requires root permissions. sudo is a commonly used tool
for granting users other than root permissions to do things like install software.
You will be prompted for the same password you use to log into your Ubuntu
user account. You will not be asked for your password again when using sudo
if you have used it in the last 5 minutes.
○ Install virtualenv and virtualenvwrapper
virtualenv is a Python package that allows us to create self-contained virtual
environments in which we can install packages without conflicting with other
environments on our system. virtualenvwrapper is another package that adds additional
functionality to virtualenv in order to make it easier to use.
■ To install virtualenvwrapper, which will also install virtualenv, type:
$ sudo pip install virtualenvwrapper
■ Then, we need to set some environment variables to tell virtualenvwrapper where
to store, find, and run information. Open up ~/.bashrc by typing:

8
$ gedit ~/.bashrc
gedit is simple text editor to use, but it is not fully featured. Consider getting
familiar with a more robust text editor like Emacs
(http://www.gnu.org/software/emacs/) or Vim (http://www.vim.org/).
The .bashrc file contains all the configuration settings for the terminal. Any
settings added to this file will be loaded every time you open a terminal
window.
■ At the end of the file, add the following lines:
$
$
$
export WORKON_HOME=~/Envs
mkdir -p $WORKON_HOME
source /usr/local/bin/virtualenvwrapper.sh
■ Save the file by pressing CTRL+S. Close the file. Then, reload the terminal
window by typing:
$ source ~/.bashrc
○ Start a virtualenv
■ To create a new virtualenv, type:
$ mkvirtualenv test_env
■ The command line should now be prefaced with (test_env),indicating that you’re
working inside a virtual environment.
Figure 2: Terminal window inside of a test_env virtual environment
When you open a new command terminal window, you can enter an existing
virtualenv (in this case test_env) by typing:
$ workon test_env

9
For the official virtualenv documentation, visit:
http://virtualenv.readthedocs.org/en/latest/
● Setup version control
Version control allows us to work on multiple versions of our code at the same time. We use git
as our source management system.
Git Immersion is a great tutorial for becoming familiar with using Git:
http://gitimmersion.com/
Github also has a detailed help section: https://help.github.com/
○ To install git, type:
$ sudo apt-get install -y git
○ Then, set up your git configuration with your name and email information. This
information will show up in the git logs and on Github. Type:
$
$
git config --global user.name "YOUR NAME"
git config --global user.email "YOUR EMAIL"
● Set up SSH with Github
Github is a web-based service that allows us to host our code in a centralized location. By using
git locally, we can pull changes,push updates, and review our code on Github. Github uses SSH
keys to securely identify trusted computers without the need for passwords.
SSH stands for Secure Shell. It is an encrypted network protocol that allows two
networked computers to securely connect to one another and authenticate each
other’s identities. Github uses SSH to identify users and to transmit data
securely between users’ local machines and their servers.

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○ If you do not have a Github account already, sign up for one at: https://github.com/
○ Then, add your newly generated SSH key to your Github account. On the menu bar, click
on the Account Settings icon (it is in the upper right-hand corner of the screen).
Figure 3. Github account settings
○ To generate an SSH key, type:
$ ssh-keygen -t rsa -C "your_email@example.com"
The command prompt will ask for the file to store the key in. Press Enter to store the
key at the default location. The prompt will also ask for a passphrase. Enter a passphrase
that you will remember. It should be at least 12 characters long contain upper and
lowercase letters, numbers and symbols.
Figure 3: Output of ssh-keygen command
○ Next, add the SSH key to the ssh-agent by typing:
$
$
eval "$(ssh-agent -s)"
ssh-add ~/.ssh/id_rsa
○ Copy the contents of the key to your clipboard by typing:
$
$
sudo apt-get install -y xclip
xclip -sel clip < ~/.ssh/id_rsa.pub
The clipboard may time out after about 10 minutes. If so, you will need to recopy
the contents of the key using the above command.

11
○ Then, click the SSH keys option on the left sidebar. Click Add SSH Key,which will
open a new form. Add a title that describes the computer you’re working on. Afterwards,
paste the key into the Key field. Finally, click the add key button.
Figure 4. Adding SSH key
○ Test that you can connect to Github via SSH by typing:
$ ssh -T git@github.com
○ The first time you run this code, you will see a warning:
Figure 5. Testing connection to Github via SSH
Simply type yes. There will be a confirmation message letting you know that you have
authenticated with Github.
Figure 6. Response upon successful authentication to Github
● Run the code
○ The code for our company website is stored on Github. In this section we will pull the
code from the website to our local machine and run it locally. To retrieve the code, it
must be cloned from the Github repository. First, make sure you are in your home
directory by typing:
$ cd ~

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○ To retrieve the code, type:
$ git clone git@github.com:stemchan/google-flask.git
○ A new folder should show up in your home directory containing the new project. Change
folders directory by typing :
$ cd ~/google-flask
○ Then, install the packages required for the project. The packages and their versions are
stored in the requirements.txt file. Type the following:
$ pip install -r requirements.txt
○ Once the packages have installed successfully, you can now run the project and view the
website that the code generates. To start the server, type:
$ python google-flask.py
○ To test that the project is running successfully, go to a web browser and go to the url:
localhost:5000. The company homepage should appear (see Figure 6).
Figure 6. Company homepage
○ The terminal should display the following information:
Figure 7. Terminal output when running the server
○ To stop the server,press: CTRL+C in the terminal.

13
Summary
After completing these instructions, you should have a Python development environment setup on
your computer. Now that you have this environment, you will be able to write, run, and contribute to the
company’s codebase.

14
Troubleshooting
● pip error: permission denied
○ A common error many people make when first using their development environment is not
paying attention to their use of their virtual environment. If you receive an error saying you
do not have permissions to install a package with pip, it means that you are not in your virtual
environment.
Solution:Make sure you run this command every time you start work on the dev environment in a
new terminal window:
$ workon test_env
● Permission Denied (publickey)
○ There are a number of things that could potentially go wrong when creating a secure
connection with Github.
Solution: Make sure to read the Section 5 carefully to ensure that you have properly set up SSH.
If the issue still persists, refer to this help page by Github: https://help.github.com/articles/error-
permission-denied-publickey

15
Additional Resources
● Python Documentation - https://www.python.org/
● Python Tutorial - http://learnpythonthehardway.org/
● Command Line - http://cli.learncodethehardway.org/book/
● Virtualenv - http://virtualenv.readthedocs.org/en/latest
● Virtualenvwrapper - http://virtualenvwrapper.readthedocs.org/en/latest/
● Git - http://gitimmersion.com/
● Github - https://github.com/

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