Jun 08, 2025 Jun 08, 2025

Setting up a Virtual Environment by venv

Since Ubuntu 24.04 (noble) it is not possible anymore to install Python-packages into the system's Python without forcing it with the --break-system-packages flag, and we are going to respect that. Either we install the missing package as Ubuntu-package (sudo apt install python3-PACKAGE) or we create a virtual Python environment. Generally the version behind Ubuntu-Packages will never exceed those from the original Python-Packages; thats why we are focusing on the latter, the virtual solution.

Basic Set-up & Usage

To create an virtual Python environment by venv (natively included in the system's Python) execute following command inside the Terminal:

Terminal

python3 -m venv PATH_OF_ENVIRONMENT

The NAME_OF_ENVIRONMENT ist also the name of the directory. Now jump to PATH_OF_ENVIRONMENT/bin/, open the Terminal from there (F4) and activate the environment by

Terminal (PATH_OF_ENVIRONMENT/bin/)

source ./activate

From there on you can run the commands for python3, pip3 and so on by directly tipping it into the Terminal independently of the working directory, in which your Terminal points.

With deactivate your Terminal will leave the environment turning back to the system's Python.

Advancing the Set-up: Python-venv to global PATH variable

To comfortably access multiple environments by a custom Terminal-Command from anywhere, it is recommended at least to create one "helper-file" (e.g. vhelper) and modify an already existing system-file (.profile).

Goal is to implement a new Terminal-Command (by a helper-file called "vhelper") which automatically recognizes all Virtual Python-Environment present inside a directory and can be each activated by its foldernames. When the name of VEnv is chosen to be called "NAME_OF_ENVIRONMENT", then this VEnv shall be activated simply by following Terminal-Command:

Terminal

vhelper NAME_OF_ENVIRONMENT

These are the expected directory-structure & command-usage for the following scenario:

Scenario-example

Collection of virtual environments (folder):    $HOME/.venv

New virtual environment (folder):               $HOME/.venv/NAME_OF_ENVIRONMENT

Terminal-Command to activate the environment:   vhelper NAME_OF_ENVIRONMENT

To create an virtual Python environment jump to $HOME/.venv, open the Terminal from there (F4) and execute following command:
Terminal
```
python3 -m venv NAME_OF_ENVIRONMENT
```

Create File (vhelper) at $HOME/.venv and add these lines...

$HOME/.venv/vhelper

#!/usr/bin/env bash

if [ -f "$HOME/.venv/$1/bin/activate" ]; then
    ENV_PATH="$HOME/.venv/$1/bin/activate"
    bash --rcfile $ENV_PATH -i
else
    echo 'Error: No Python-Environment found with the name "'$1'" '  
fi

Grant execute permission to your file
Terminal
```
sudo chmod +x $HOME/.venv/vhelper
```
Either export that base folder path so that you can find it on command-line by clicking tab...
Terminal
```
PATH=$PATH:"$HOME/.venv"        (only valid for Terminal-session)
```
or

for global recognizion on each system-start (permanent solution) open $HOME/.profile and insert following lines:
$HOME/.profile
```
if [ -d "$HOME/.venv" ] ; then
    PATH="$HOME/.venv:$PATH"
fi 
```
after OS-restart vhelper-script will be recognized by the OS-Terminal
Now you can use it from anywhere by just typing the command...
Terminal
```
vhelper NAME_OF_ENVIRONMENT
```
Deactivate the VEnv-session by exit or deactivate (exit preferred. Terminates process)
Optional: If you would love to keep the Terminal-format and -color of the prompt after switching to the VEnv, then customize the file "activate" inside the bin-folder and insert following new line export PS1= ... after line 50:
$HOME/.venv/NAME_OF_ENVIRONMENT/bin/activate
48 49 50 51
_OLD_VIRTUAL_PATH="$PATH" PATH="$VIRTUAL_ENV/bin:$PATH" export PATH export PS1='\e[1;32m\u@\h\e[0m:\e[1;94m\W\e[0m$ '

General Note: Don't change the foldername of the VEnvs, so make sure to check their spelling before executing their creation.

Usage & Results

Open the Linux-Terminal (Win + T) and activate your Python3-Venv (NAME_OF_ENVIRONMENT = base) by your custom set command: