Pipenv & Virtual Environments

    It will show you how to install and use the necessary tools and make strongrecommendations on best practices. Keep in mind that Python is used for a greatmany different purposes, and precisely how you want to manage your dependenciesmay change based on how you decide to publish your software. The guidancepresented here is most directly applicable to the development and deployment ofnetwork services (including web applications), but is also very well suited tomanaging development and testing environments for any kind of project.

    Note

    This guide is written for Python 3, however, these instructionsshould work fine on Python 2.7—if you are still using it, for some reason.

    Before you go any further, make sure you have Python and that it’s availablefrom your command line. You can check this by simply running:

    You should get some output like . If you do not have Python, pleaseinstall the latest 3.x version from python.org or refer to the section of this guide.

    Note

    If you’re newcomer and you get an error like this:

    1. >>> python
    2. Traceback (most recent call last):
    3.   File "<stdin>", line 1, in <module>
    4. NameError: name 'python' is not defined

    Additionally, you’ll need to make sure you have pip available. You cancheck this by running:

    1. $ pip --version

    If you installed Python from source, with an installer from , orvia Homebrew you should already have pip. If you’re on Linux and installedusing your OS package manager, you may have to separately.

    Pipenv is a dependency manager for Python projects. If you’re familiarwith Node.js’ or Ruby’s bundler, it is similar in spirit to thosetools. While can install Python packages, Pipenv is recommended asit’s a higher-level tool that simplifies dependency management for common usecases.

    Use pip to install Pipenv:

    Note

    This does a user installation to prevent breaking any system-widepackages. If pipenv isn’t available in your shell after installation,you’ll need to add the ’s binary directory to your PATH.

    On Linux and macOS you can find the user base binary directory by runningpython -m site —user-base and adding bin to the end. For example,this will typically print ~/.local (with ~ expanded to theabsolute path to your home directory) so you’ll need to add to your PATH. You can set your PATH permanently bymodifying ~/.profile.

    Pipenv manages dependencies on a per-project basis. To install packages,change into your project’s directory (or just an empty directory for thistutorial) and run:

    1. $ cd myproject
    2. $ pipenv install requests

    Pipenv will install the excellent library and create a Pipfilefor you in your project’s directory. The Pipfile is used to track whichdependencies your project needs in case you need to re-install them, such aswhen you share your project with others. You should get output similar to this(although the exact paths shown will vary):

    1. Creating a virtualenv for this project...
    2. Using base prefix '/usr/local/Cellar/python3/3.6.2/Frameworks/Python.framework/Versions/3.6'
    3. New python executable in ~/.local/share/virtualenvs/tmp-agwWamBd/bin/python3.6
    4. Also creating executable in ~/.local/share/virtualenvs/tmp-agwWamBd/bin/python
    5. Installing setuptools, pip, wheel...done.
    6.  
    7. Virtualenv location: ~/.local/share/virtualenvs/tmp-agwWamBd
    8. Installing requests...
    9. Collecting requests
    10.   Using cached requests-2.18.4-py2.py3-none-any.whl
    11. Collecting idna<2.7,>=2.5 (from requests)
    12.   Using cached idna-2.6-py2.py3-none-any.whl
    13.   Using cached urllib3-1.22-py2.py3-none-any.whl
    14. Collecting chardet<3.1.0,>=3.0.2 (from requests)
    15.   Using cached chardet-3.0.4-py2.py3-none-any.whl
    16. Collecting certifi>=2017.4.17 (from requests)
    17.   Using cached certifi-2017.7.27.1-py2.py3-none-any.whl
    18. Installing collected packages: idna, urllib3, chardet, certifi, requests
    19. Successfully installed certifi-2017.7.27.1 chardet-3.0.4 idna-2.6 requests-2.18.4 urllib3-1.22
    20.  
    21. Adding requests to Pipfile's [packages]...
    22. P.S. You have excellent taste! ✨ ? ✨

    Now that Requests is installed you can create a simple main.py file touse it:

    Then you can run this script using pipenv run:

    1. $ pipenv run python main.py

    You should get output similar to this:

    1. Your IP is 8.8.8.8

    Using $ pipenv run ensures that your installed packages are available toyour script. It’s also possible to spawn a new shell that ensures all commandshave access to your installed packages with $ pipenv shell.

    Congratulations, you now know how to install and use Python packages! ✨ ? ✨