Python Venv

Python Virtual Environment (venv)

This skill helps you create and manage isolated Python virtual environments.

Creating a Virtual Environment

Step 1: Install venv (if needed)

On Debian/Ubuntu systems, install the venv module:

sudo apt-get install python3-venv

Step 2: Create the environment

Navigate to your project directory, then create the venv:

python3 -m venv <environment-name>

Example:

python3 -m venv pvenv

This creates a folder called pvenv containing your isolated environment.

Step 3: Activate the environment

source <environment-name>/bin/activate

Example:

source pvenv/bin/activate

Your shell prompt will change to show the environment is active (typically prefixed with the environment name).

Step 4: Install packages

Now you can install Python packages without affecting your system Python:

pip install <package-name>

Step 5: Deactivate when done

deactivate

Common Issues

Error: invalid command 'bdist_wheel'

If you encounter this error when installing packages:

error: invalid command 'bdist_wheel'

Fix it by running inside your virtual environment:

pip3 install wheel

Best Practices

• Create a venv for each project to keep dependencies isolated
• Add the venv folder to .gitignore to avoid committing it
• Use descriptive names for your environments (e.g., project-venv, data-analysis-env)
• Activate before installing any packages to ensure they go into the right environment

Quick Reference