Use different Python version with virtualenv

Question

I have a Debian system currently running with python 2.5.4. I got virtualenv properly installed, everything is working fine. Is there a possibility that I can use a virtuale

Answer 1

Here is the stepbystep how to create the Virtual environment in Visual Studio Code folder: I used Powershell (Administrator mode):
1. I create a VSCode folder - "D:\Code_Python_VE" where I want to create Virtual environment.
2. Next I type the command - "pip3 install virtualenv". (D:\Code_Python_VE> pip3 install virtualenv) 3. D:\Code_Python_VE> python3 -m venv project_env
4. D:\Code_Python_VE>project_env\Scripts\activate.bat
5. D:\Code_Python_VE> ls - This will list a new directory "project_env".
6. D:\Code_Python_VE> code . This will start Visual Studio Code. Make sure the command is (code .).
7. Create launch.jason with following content:

{
    // Use IntelliSense to learn about possible attributes.
    // Hover to view descriptions of existing attributes.
    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
    "version": "0.2.0",
    "configurations": [
        {
            "type": "python",
            "request": "launch",
            "name": "Python: Current File (Integrated Terminal 1)",
            "program": "${file}"
        },
        {
            "name": "Python: Current File (Integrated Terminal 2)",
            "type": "python",
            "request": "launch",
            "program": "${file}",
            "console": "integratedTerminal"
        }
    ]
}

(Please search how to go to Debug window and Add new Configuration in VS Code).

8. Press F1 in Visual studio code and the command pallet will open - Select Python Interpreter and select the virtual environment project_env.
9. Add test.py file with one statement print("Hello World").
10. Run this program.
11. In Visual studio Code terminal -
    (project_env) d:\Code_Python_VE>python -m pip install --upgrade
    I hope this helps.

Answer 2

For Debian (debian 9) Systems in 2019, I discovered a simple solution that may solve the problem from within the virtual environment.

Suppose the virtual environment were created via:

python3.7 -m venv myenv

but only has versions of python2 and python2.7, and you need the recent features of python3.7.

Then, simply running the command:

(myvenv) $ python3.7 -m venv --upgrade /home/username/path/to/myvenv/

will add python3.7 packages if they are already available on your system.

Answer 3

virtualenv --python=/usr/bin/python2.6 <path/to/myvirtualenv>

Answer 4

You can call virtualenv with python version you want. For example:

python3 -m virtualenv venv

Or alternatively directly point to your virtualenv path. e.g. for windows:

c:\Python34\Scripts\virtualenv.exe venv

And by running:

venv/bin/python

Python 3.5.1 (v3.5.1:37a07cee5969, Dec  5 2015, 21:12:44) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>>

you can see the python version installed in virtual environment

Answer 5

For Mac(High Sierra), install the virtualenv on python3 and create a virtualenv for python2:

 $ python3 -m pip install virtualenv
 $ python3 -m virtualenv --python=python2 vp27
 $ source vp27/bin/activate
 (vp27)$ python --version
 Python 2.7.14

Answer 6

Even easier, by using command substitution to find python2 for you:

virtualenv -p $(which python2) <path/to/new/virtualenv/>

Or when using virtualenvwrapper :

mkvirtualenv -p $(which python2) <env_name>