Virtual Environments with venv

Table of Contents

What is a Virtual Environment

A virtual environment is an isolated environment where the Python interpreter, libraries and scripts installed are kept completely separate from other environments including the system environment installed on your operating system.

Creating a Virtual Environment with venv

Since Python 3.3. Python has included venv in its standard libraries. To create a virtual environment with the name name_of_venv type python -m venv name_of_venv

Activating a Virtual Environment

To activate the virtual environment type name_of_venv\Scripts\activate python

The command line interface will now start with (name_of_venv) to show you it has been activated.

You can now install packages with pip: pip install jupyter

Deactivating a Virtual Environment

To deactivate the virtual environment type deactivate

Add the Virtual Environment as a Python Kernel in Jupyter

Jupyter uses the default system IPython kernel but you have to manually add a kernel for the virtual environment you just created.

To add the virtual enviroment to Jupyter, first you need to:

1. activate the environment
2. install jupyter (which includes the library ipykernel)
3. type python -m ipykernel install --user --name=name_of_venv

List Kernels added in Jupyter

type jupyter kernelspec list

Remove a Kernel

type jupyter kernelspec remove name_of_venv

References

• venv Docs
• IPython Docs

#Versions used in this notebook
import sys
print("OS:", sys.platform)

!python --version

from importlib.metadata import version
for library in ["jupyterlab"]:
    print(library, version(library))   

OS: win32
Python 3.9.1
jupyterlab 2.2.0