Python - pyenv and venv

A Little Background !

When I started learning Python and started using it’s various libraries and Frameworks, like most of the beginners I never cared about where I am installng those packages and what problems they are going to create in future.

After few days I got to know about the concept of creating virtual environment for each of our projects, so I started using that, but it was still incomplete. We’ll see how!

For those who don’t know what is virtual environment :

In simple terms you can understand, that we create a environment for our project and then whatever package we install is installed locally, at that project level, not globally.

Why is it even required ?

Suppose we are working on Project A which requires version A of Django , we installed that globally. Now for project B which, suppose, uses Version B of Django things will get worse.

Your Project will not find the correct version it needs to operate and you will get weird errors.

Process I follow for managing Python Projects in my Machine.

Use pyenv to manage different version of Python in your machine.

Use venv to create and use virtual environment.

Let’s me tell you the steps :

• Install pyenv to your machine. [One Time]
• Install as many Python Versions you want using pyenv install version
• Set up one of the version as global using pyenv global version, by default it is system (don’t use that) [One Time]

Now suppose we want to create a project

• Head over to that directory
• Use pyenv local version to declare which python version you want to use for that project.

Previous step will create a .python-version file containing the python version as text.

• Using python -m venv virtualenvname we create a virtual environment.
• Using source virtualenvname/bin/activate, we activate the venv.
• Now install any python package you want to install using python -m pip install pkgname

Hence we setup a project which uses a specific python version of our need.

Also we created a venv so that packages are installed locally, not globally hence no version conflicts in future.

Frequently used commands

• pyenv install version : To install a python version
• pyenv local version : To use specific python version in your project
• python -m venv venvname : To create Virtual environment.
• python -m pip install packagename : To install packages

Resources :

• Install pyenv

• How it works

  Tips for installation:

  • Complete the prerequisite given.
  • Use the Github Checkout Method.
  • Make sure to Logout and Login then only changes will take place.

• Nice Blog