Virtualenv supports the creation of isolated Python environments. This allows you to create your project with all of it's dependencies in one place. Not only does this allow for a simpler deployment path when you release your project but it also makes trying different versions of libraries and experimenting safer.
The following is a good intro for virtualenv.
Step 1 is to install virtualenv. When you run the following you'll be installing virtualenv on your machine.
$ pip install virtualenv
You should be able to execute the command virtualenv afterwards.
When you can you can move on.
Here is how I use virtualenv
I create my project directory such as:
$ cd /home/brad/projects/ $ mkdir example $ cd example
Then I setup a virutal environment for this project with the following command:
$ virtualenv env
This differs from the site mentioned above. I do the same for every project so when I'm in each of my project directories they all have an
env directory. Then everything is the same. This keeps things simple and easily remembered.
To start the virtual env you run the following from the project directory
$ source ./env/bin/activate
Once your virtual environment is activated anything you install will be put into the environment. If you look you'll notice new directories inside of
./env/lib/python2.7/site-packages after each install.
Now, install what you need. For example,
$ pip install zipline
To see all the libraries in your environment you can run
$ pip list
When you run python in your active environment you'll have access to all the libraries you've just installed.
Lastly, to get out of the virtual env you can run